Kyoukai Senjou no Horizon - Volume 8A, Chapter 8: Regretters on the Hill

Doomsday crisis, zombies are attacking, the situation is critical.Don't let our enemies change from zombies coming at us to humans we protect behind us.“Brother, what would you do if I turned into an irredeemable zombie?”“…kill you.”“Then do you know what I would do if you turned into a zombie?”“Kill me.”“No,” he lifted her long hair, revealing her smooth neck.“You are crazy. I advise you to give up this irrational idea.”“Brother, this world has gone crazy.”

"Stay with me and I will give you everything your heart desires. For you, my darling, I would part the mountains, split the sea, and cause havoc on Earth just to have you."

This is actually the story of a teenager who, after the devastating and spartan-like training of his crazy cool/Gong teammate, turned into a super amazing point guard that could blow up the skies even though he may seem low-key on the surface.

Also, Nie Chuan is Reese’s first love.

Nie Chuan: I’ve decided to promote you to becoming my best friend!

Reese: If I can be your best friend, it just means that you have no friends.

Nie Chuan: Hey! How could you say that! Do you know what it means to be my best friend?!

Reese: I’m sleeping.

Nie Chuan: It means that when I get married, my bride may not necessarily be her, but my groomsman must be…

Reese: The groom must be me.

Nie Chuan: What– you want to snatch my bride away?! You’re too inhumane!

Reese: Sleep.

- Description from Novelupdates

When 18-year-old Kyle Conner arrives at his aunt's for a summer holiday, he expects relaxation and freedom. Instead, his life is forever altered when he crosses paths with Lilith, the demon of lust and second-most powerful entity in the underworld.Forced into a dark pact, Kyle is transformed into a demon and gifted with a mysterious system that promises immense power. But this newfound strength comes with a deadly price: Kyle must hide his true nature and navigate the treacherous world of demons, all while being hunted by Lucifer and other malevolent forces.As Kyle struggles to control his newfound powers and unravel the secrets of the system, he discovers his ultimate goal: to overthrow Lucifer and bring about a new era of peace. But with the forces of darkness closing in, Kyle must confront the darkness within himself and make impossible choices to survive.Will Kyle be able to master his demonic powers, outwit his enemies, and fulfill his destiny? Or will the weight of his newfound responsibilities consume him, dooming humanity to eternal darkness?