I don't go down without a fight, or at least some sweet talk first.
Cain LaRue is a boy from the Byxbysion Wasteland, where he lived with his mother and his older sister Aya. He is considered one of the player's rivals, along with Victoria and Fern.
Cain is undoubtedly a flirt, especially to the player. He would chime in innuendos and jokes at any given moment. Cain doesn't seem to take things seriously in a daily basis, but will mostly drop that attitude when someone is in trouble. He seems to have an instinct to look out for younger kids, especially Heather and Shelly.
Cain is first met at the Grand Hall, shortly after the player has chosen their starter Pokemon, and he will flirt with the player - regardless of the player's chosen gender - before challenging them to their first battle, after which Cain happily takes it upon himself to show the player around the Grand Hall. He then leaves the player to speak with Ame while the player battles Victoria. After the battle, Cain informs the player and Victoria that they can speak to Ame to get their basic starting gear (Pokeballs, Running Shoes, Etc.) and leaves.
Cain is not encountered again until the player reaches the Coral Ward. Here, Cain arrives just in time to help Amaria save a Popplio (Oshawott prior to Episode 17) stranded up in the water. Sending his Grimer (Which is an Alolan Grimer from Episode 17 onwards) to safely navigate the poisonous waters (and singing a heroic song all the while), Cain manages to rescue the Popplio. At first, Cain is content to just head on his way, but when the Popplio continues to follow him, Cain gives into its adorable appearance and adds it to his team, despite using a Pokemon that is not a Poison-type, and has a battle using it against the player to calm its jitters.
The player's 3rd encounter with Cain is after beating Shelly as the player has to go to inform Ame that they need to get ahold of Reborn's backup Poison leader in Byxbysion Wasteland, which happens to be Cain's sister, Aya. However, the player finds that A: Fern beat them to it + B: The player needs to find Cain who has the key to enter. The player will then find Cain at the Beryl Ward - More specifically at the cemetery east of the gym - where he is paying respects to Corey (The previous Poison leader) and decides to let the player have the key if they beat him in a battle.
However, once the battle is over, the player will learn that Cain is going to attempt to keep an eye on Corey's daughter - Heather - but it turns out that she overheard their conversation. She then argues with Cain about being old enough to take care of herself before she runs off to find Shelly in the Lapis Ward.
Cain and the player then follow Heather to Shelly's gym where Heather is trying to get Shelly to agree that she doesn't need help from any adults. Shelly doesn't feel comfortable being put in between her friends' opinions and doing the right thing though, causing Heather to feel betrayed and storm out with Cain, the player, and Shelly on not far behind. Things take a turn for the worse though as Heather runs into Dr.Connal who runs the Lapis Ward Orphanage, where he uses the law to get everyone else to back off and to take Heather into the orphanage.
The trio returns to Shelly's gym after realizing they'd be breaking the law by opposing Dr.Connal and are stuck wondering what to do now. This contemplative moment is cut off though as they hear screams from the orphanage that belong to Heather. Hearing this the trio decides to break into the orphanage and get Heather out - regardless of the consequences. It is here that the player, Cain, Shelly, and three of the orphans already within the orphanage - Charlotte, Anna, and Noel - decide to rescue Heather and escape.
Cain and Shelly then guide the group to the underground rail net where they plan to escape from Reborn city to where Charlotte used to live with her sisters - Saphira and Laura - in the Chrysolia region. Unfortunately, the player has to beat Shade, Reborn's Ghost Type Leader, to re-power the gate so they can all escape and splits from Cain and the group.
Once the player does beat Shade the gate opens, only for the ghost type leader to show on the rail net cameras that Team Meteor - who has now teamed up with Dr.Connal - captured everyone except Cain in an ambush. However, Cain has to destroy the path to the gate with his Nidoking and the only other way out requires Strength - which neither Cain nor the player has. The player then follows Cain to get the TMX for Strength from Kiki, Reborn's Fighting Type Leader, but Cain uses his Muk to cross the toxic waters of Azurine Lake and leaves the player behind to catch up, however they can.
The next time the player does see Cain is shortly after beating Kiki. Victoria states that he never showed up to the island while the player was trying to find their own way across. As such the player goes to Azurine Island as it is the only place he could be. Once the player does arrive at Azurine they find Cain's earring on the ground which lets the player know he is, in fact, on the island somewhere. The player then finds out that Taka - one of Team Meteor's admins - is holding him prisoner after they find a Team Meteor base on the island. Taka then reveals to both of them they are going to use a Pulse Camerupt to make Pyrous Mountain erupt and wipe out those that inhabit Apophyll Academy.
With this information, the player and Cain go to Apophyll academy to warn Kiki and Victoria. It is then that the player and Cain lead a charge up Pyrous Mountain to prevent the destruction of the Academy. After the events of Pyrous Mountain, the player and Cain promise Victoria that they will beat the Reborn League for her due to Victoria suddenly becoming the new sensei. Cain later opens the gate to Byxbysion Wasteland for the player's next gym badge and waits for the player in the Underground Railnet.
Aya later reveals that he was originally supposed to be the back-up leader for the Blight Badge, but decide to run away and dump the job on her instead. Cain reveals he ran away because of his disagreement with his mother over his sexuality. He knows what its like to be alone, which is why he want to go save the kids. After rescuing the kids from the Yureyu Building, Cain continues through the Underground Railnet with the rest of the group, eventually taking control of the train that the group use to break through the rubble there, emerging in the Chrysolia Region.
Upon exiting the train, Charlotte leads the group to Belrose Mansion - the family home of her and her sisters - via Tanzan Mountain. Heather however decides to fly off with her Salamance, Cain decides to follow Heather to make sure she's okay, breaking off from the group.
This article contains plot details about events that occur later in the game.
Cain later reappears in Vanhanen Castle to challenge the gym leader Radomus. He mentions that Heather is now safe with a man named Blake, and is back to challenging the gyms. Now stuck with two challengers, Cain then decides that the Player and him should battle to decide who will fight him first.
After this battle Luna then receives a message saying how Gardevoir, who has been conspicuously missing since Radomus dismissed her and Luna earlier, has been captured by El who insist that his daughter is returned to him. Despite Radomus' proposal that the group should do nothing about this Cain angrily insist that they go after El and Gardevoir before leaving to do so. Radomus still has no intention of going of to save her however this changes when Luna asks him to find Gardevoir and as such he and the player follow Cain.
Eventually the Radomus, Cain and the player arrive at the Grand Gates, which have closed off access to Reborn City for over 10 years. El flees past one of the large gears beside the gates and deep underground into the same caverns found when Team Meteor blew up The Grand Stairway. The trio follow him until they reach a much more ample and fertile space full of sophisticated ruins and a large tower. Here the group run into Gossip Gardevoir along with a silver haired person name Adrienn. Gardevoir then steals the Amethyst Pendant from the player, which Randomus also seems to recognise, and flees with Adrienn and El up the Amethyst pathway in the central tower using said pendant. The trio then give chase using the Ruby Ring to enter the Ruby pathway (They also pick up Adrienn along the way as they are left behind by El and Gardevoir) however along the way Cain and The Player get suspicious of Radomus due to what Gardevoir and Adrienn had said prior.
Radomus, Cain, Adrienn and The Player all meet up with El at the entrance to the central tower. El tells the group about how a meteorite housing Arceus' power is inside the tower and how he needs the 4 keys to open it. Radomus ridicules him for this and El then argues back with how he's 'Brainwashing' Luna and mistreating Gardevoir but Radomus remains apathetic to the whole situation. After a bit more dialogue the player has to side with Radomus or El and regardless of the choice the player makes Radomus exposes El's fakery with Gardevoir being revealed to be a ditto with Radomus expressing satisfaction or disappointment if they sided with or against him respectively. After this a battle with El ensues (A/N If they player choses to side with El then they don't have to win said battle but they do have to win if they side with Radomus). Afterwards El is knocked unconscious, Gardevoir reappears and the group return above ground only to find that the grand gates are now finally open.
After explaining Adrienn's confusion about Reborn City, Cain, Radomus, Gardevoir and the player, return to Vanhanen Castle, either together or alone, for the player's battle with Radomus. Upon returning to the Castle Luna is ecstatic that Gardevoir has returned. Soon afterwards El is somewhat comically revealed in a butlers outfit under the name of 'Elias' and hands the Amethyst Pendant over to Radomus, who keeps a hold of it for now. However the appearance of El makes Luna uncomfortable along with raising suspicion in Cain and The Player as to what El had said about Radomus' 'Brainwashing' may have been in fact true. Due to her discomfort Luna leaves the main room to wait for gym challenge to begin. After this the player then challenges Radomus to a gym battle.
After beating Radomus, Luna informs the player of how they will battle in Iolia Valley before the power cuts out. The Player then leaves the gym but is captured by El, who is now free of his brainwashing/hypnosis, along with some team meteor grunts. The Player then escapes Vanhanen Castle with the help of Cain holding El off and Radomus, who is disguised as a Meteor grunt at this point. Before the player leaves Radomus is able to inform The player that Luna has been kidnapped and is most likely somewhere in 7th Street below the Lapis Ward.
Cain appears in Subseven Sanctum being held hostage by Bennet. El tells the player to not move or he will put an end to Cain's life. The player is forced to watch the ritual El preforms on Luna. Radomus and Gardevoir then interrupts the ritual on time, freeing Luna and Cain. Luna then invites the player to a gym battle and Cain decides to try to wake up the guards in Agate City.
After beating Luna, the player and Cain decides to break the gate entrance to Agate City since the guards aren't waking up. Cain spots Aya and Hardy sleeping in the center of town, with Cain starting to feel tired as well. Out of nowhere, Terra rescues the player, Cain, and a sleeping Aya and Hardy. Terra uses her giant hammer to hit Aya and Hardy towards the direction of Agate City, while guiding Cain and the player to Agate Circus.
While Hardy lands further ahead, Aya lands in the middle of the circus and is brought into the back room of the tent. Once she awakens, she's greeted by Cain, who although was the reason she was forced to take the job as the Poison-type gym leader, doesn't show any anger towards. Instead, Aya insists on finding out where Hardy landed. Cain asks if she likes Hardy, but Aya quickly denies it (although Cain doesn't believe it). Talking to Aya or Cain after the discussion further shows that even though Cain ran away and left her with the gym, Aya doesn't show any resentment towards Cain. Rather, she is somewhat thankful as she was able to meet Hardy.
After beating Samson, Terra says that the PULSE which has the city in a sleeping curse is located on top of Ametrine Mountain, Hardy, Aya, and Cain decide to head towards Calcenon City to help the other gym leaders help fend off against Team Meteor while the player will head to Ametrine City.
While the player heads towards Ametrine City, they find Aya, Cain, and Hardy looking at an enormous ice blockage in the path, being unable to break through it (Which is later discovered to be a PULSE Avalugg). With Ametrine City being trapped at the top of the mountain without supplies, the group proposes treading to Calcenon City to get help. Before climbing the stairs to enter Calcenon City, the stairs are destroyed by a stray shot from a PULSE Clawitzer. Saphira, who is currently trying to combat the PULSE, meets up with the group on her Dragonite and tells them to enter through the eastern entrance. As the group is traveling, the bridge is destroyed by a stray shot from the PULSE Clawitzer, splitting the Cain and Hardy with Aya and the player. Cain and Hardy goes on ahead and the player and Aya to team up throughout Route 3.
Cain and Hardy safely enters Calcenon City, but realize the Aya was kidnapped by Team Meteor, although Cain isn't too worried about her unlike Hardy. He still worries about her but says Aya will probably complain Team Meteor's head off instead. Cain decides to stay in Calcenon City to watch over the city and the kids. After activating TMX Fly, Cain says the twins are missing and are looking for them. Hardy later says Cain went with Shelly to look for them, but both haven't come back yet.
After getting the Torrent Badge, Hardy and the player decides to look for everyone missing with TMX Rock Climb. It turns out Cain and Shelly in the Glass Workstation, but are brainwashed to fight the player. After the player beats Cain and Shelly, the player blacked out by a PULSE Hypno, battled something and wakes up in a black, void-like area with stars around.
Cain later appears in here as the real person, saying the player probably looked at his past, which was his parents getting divorced and him leaving Aya. He reveals that wants to forget about the past, which is why he ran away, but realize he's running in circles. He doesn't know what to actually do with his life, while everyone he met seem to know what they want in the future. All of his jokes and flirts were ways to keep himself safe from commitments and disappointments, trying to find a place where he belongs. He stays in the void to do some serious thinking, but jokes the player to give him a call later.
When put together with Aya, Cain's name is a word play on “iocane”, a fictional poison from The Princess Bride. Cain's name can also be a biblical reference, chosen because Cain betrays his sibling and runs away from his responsibilities.
Cain flirts with anyone (Charlotte and Adrienn), regardless of gender. But he mainly flirts with the player.