(A/N: Requested by ZetaRaiser, and it's actually Yandere Cheater Union Harem X Bullied/Cheated Getter Emperor Male Reader X Yandere Loving and Caring Azur Lane/Genshin Impact/FGO/Kuroinu Harem & Yandere Loving and Caring Rias/Akeno/Xenovia/Yasaka/Ravel/Kuroka/Koneko (Lemon))
(Y/N L/N is a student in Union Academy, who was down in his luck. He was basically bullied a lot by everyone, except for the shipgirls, the Kuroinu Knights, Olga Discordia, Chloe, Teyvat Group, Chaldea Group, Rias Gremory, Akeno Himejima, Xenovia Quarta, Yasaka, Ravel Phenex and Koneko Toujou. Kuroka cared about Y/N as well, especially after he found out that his girlfriends were cheating on him.)
New Jersey: How could they do this?
Alicia: The nerve of those bitches...
Amber: They'll pay for this.
Mash: And dearly.
Rias: Don't worry, Y/N. You have us.
Koneko: Yeah, thanks to you, I reunited with my sister.
Kuroka: It's good to reunite with you, sister. Nya.
Xenovia: Yeah, fuck that pathetic red lizard. You're our destined one, not him.
Akeno: Agreed. His arrogance made him outlive his usefulness.
Yasaka: How about we show you a good time?
Ravel: Sounds like a good idea.
(Then they strip naked and Y/N gets an erection.)
Akeno: Ara ara~ someone is already happy to see us.
(Claudia walks up to him, unzips his pants and the girls see his erected member.)
Claudia: Wow, never thought you could be so big.
Rias: Good thing we saved our first for you.
(Claudia and Rias start licking his manhood.)
Claudia/Rias: You taste good.
(They decide to massage his manhood with their breasts while Koneko makes out with Y/N.)
Rias: Does it feel good?
(Y/N gives them a thumbs up.)
Claudia: I guess that's a "yes".
(Then Rias sits on Y/N's lap and inserts his manhood into her womanhood.)
Rias: I wanted this ever since I realized my love for you.
(Koneko then stops making out and sits on Y/N's face, smirking at Claudia, who pouts. Koneko rubs her womanhood in Y/N's face while Rias moves really fast. The two even make out as Y/N licks Koneko. After some minutes, they cum, and then Claudia takes Rias' place while Akeno takes Koneko's. But she places her left bosom instead.)
Akeno: Come and get mommy's milk.
(Y/N starts sucking Akeno's bosom while Claudia bounces on his manhood really fast.)
Claudia: Wow, you feel so great.
(She moves faster while Y/N sucks Akeno's bosom harder, making her moan, and both Y/N and Claudia cum. Beidou and Jeanne D'Arc take Claudia's place as they rub their pussies on his dick before Chloe pushes Akeno and sits on Y/N's face, making him lick her pussy as she rubs it on his face.)
Chloe: Does my pussy taste good?
(Beidou and Jeanne decide to rub their butts on his manhood, and Y/N eventually sprays on them while Chloe cums on his face.)
Akagi: You know we can do this all day, right?
Yorktown II: Ready for some more, hotshot?
Hornet II: We'll have so much fun in this young night.
(Yorktown II inserts Y/N's manhood into her womanhood while Hornet II sits on his face, having him lick her.)
(Y/N had sex with his new girlfriends for the rest of the day.)
(Next day Y/N had decided to pilot his mech known as Getter Emperor. He easily defeated Team CRDL, Satsuki, Elite Four, Class 1-A and 1-B Boys. Meanwhile Rias killed Issei and took his sacred gear from him.)
Rias: I should never have revived you!
(The Kuroinu Knights are seen brutally beating 1-A and 1-B girls.)
Prim: You should really feel ashamed of yourselves. Now you lost him forever.
Ibara: No...
Momo: We want Y/N back...
Maia: You don't deserve him!
(They then kill the girls. The Shipgirls are seen shooting Weiss, Yang and Nora down.)
Nora: Damn... if we broke those abominations' legs, we'd have Y/N back with us...
Kaga: You dare call us abominations? That's unacceptable!
(Kaga kills all of the huntresses without any mercy. Back to Getter Emperor, he is seen easily defeating several Union Students.)
Y/N: GETTER BEAM!
(Getter Emperor easily pulverizes Saji, Riser, Team SSSN, Jaune, Ren, Mirio, Tamaki, Ichika, Tatsumi, Lubbock, Susanoo and Bulat. Then he turns to the Headmasters as he charges his full power into an energy ball.)
Y/N: STOOOONEEEEEEER SUUUUUUUNSHIIIIIIINE!
(Y/N easily kills the Headmasters while Enterprise, Artoria (Lancer) and Olga helped Y/N against the Union.)
Enterprise: Keep moving foward!
Artoria (Lancer): Attack at will!
Olga: No mercy!
(Y/N and the girls slaughtered each and every Union Student in their way. They eventually won and Y/N has a happy life with his new harem.)