(Damian Gunnhildr is the adopted younger brother of Jean, and uses Anemo Vision along with 4 Delusions (Pyro, Cryo, Electro and Hydro) but only uses them to control the Abyssal Power he has when he fell on the Abyss during a mission. Jean, Diluc and Kaeya are the only ones who know the circumstances.)
Jean: You know... I'm worried about my brother.
Diluc: I know, right? He barely got saved from his berserk form and he became obsessive with Eula?
Kaeya: Yeah, this reminds me...
(Flashback)
(Damien is seen in his berserk form as he is defeating the Knights of Favonius, but got saved by Eula.)
(Flashback Ends.)
Jean: Yeah, since then he swore to make her his.
Diluc: Which explains so many males being murdered.
Kaeya: She became obsessive as well.
(Flashback)
(Damien is seen beating up Eula's old family.)
Damien: Who do you guys think you are? Treating a young poor girl like a doll? I hate likes of you!
(Damien keeps beating the crap out of Eula's old family, and then she forms a seductive smirk.)
Eula: (in mind) I found my destined one.
(Some minutes after the incident, Eula sees some girls trying to talk with Damien, and she grits her teeth.)
Eula: So some bitches are trying to lay their dirty hands on my love, huh? They'll pay for this!
(Once Damien left the scene, Eula takes the opportunity and kills the girls in cold blood.)
Eula: Damien is mine! MINE! HEAR ME! MIIIINE! HAHAHAHAHAHA!
(Timeskip)
(Damien and Eula meet in a room as they get close to each other.)
Damien: I have something to tell you, Eula.
Eula: What a coincidence, I have something to tell you too.
Damien/Eula: I love you!
(They then smile and have a passionate kiss.)
Eula: I knew you loved me, my sweetheart.
Damien: Same, my beautiful princess.
(Then they confess they killed some obstacles in the way of their love for each other.)
Damien: The only boys I didn't kill were from my sister's group.
Eula: Same thing about the girls in Knights of Favonius. I still see them as my friends.
Damien: Well, how about both of us becoming one.
Eula: Sounds like a good idea.
(They go to a private room and strip naked.)
Damien: I always knew you had such a beautiful body.
Eula: And you're so well toned, my love.
(They begin making out with Damien groping Eula's breast while she strokes his massive cock.)
Eula: I can't wait anymore. I want you now.
(Damien then inserts his member inside of her and thrusts in a ballet dancer position.)
Eula: (moans) Harder! Fuck me harder!
(He does so while they make out again and moan during their kiss. They keep going for hours until Damien gets close to his limit.)
Damien: Eula! I'm about to cum!
Eula: Do it inside of me! Do it! Impregnate me!
(Damien then cums inside of her.)
Eula: That was amazing. I love you, Damien.
Damien: I love you too, Eula.
(Then the two go to sleep and days later they became an official couple.)