Mash-Up Anime: Teenage Assassin Enrollment. - Chapter 10 - Alya

When an S-class elite assassin-raised captain of a special ops suicide squad comes home from a high-stakes Africa mission, he finds himself offered something that could potentially set him up for life- a curious assignment that he could use to finally exit his days of war and slaughter.

Then placed into a high-school setting, Lin Yi is tasked by the chairman of a top-tier multi-billion company with bodyguard duty for non-other than his own daughter, a certain little Miss of said high-school.

His enemies, once ranging from drug lords, mafia bosses, political figures, and national leaders, are soon replaced with spoiled kids who happen to have rich papas and mamas, and Lin Yi finds his intense expertise and high-threat skillset misused, and very underwhelmed…

But he does get a harem cast as diverse as his old enemies, so Lin Yi decides that, for the sake of messing around with girls as an invincible entity in a down-leveled environment, leaving his bloody and death-filled war days behind is something he’d definitely want to strive for.

- Description from Novelupdates

[Nakseong High School, the heads of 300 people exploded!] Lee Joon, an ordinary high school student.During the entrance ceremony, he was caught up in a strange phenomenon and died.[You have died.] [Restarting from checkpoint.] [Loading…] And then a message appeared before his eyes.『Welcome to Nakseong High School that is full of mysteries and secrets.Uncover the dark secrets hidden around the school, or fight against urban legends and myths to earn points and unlock special abilities.Then, gather companions and stop the resurrection of the demon king before you graduate.The world is in your hands.』

Chen Tong is punished by a Demon God to go to each world to be various kinds of spirits, fortunately regardless of what to cross, he is good at using demon spirit magic, healing, prophecy, psychic, all kinds of strong flaunting off isn’t good.

The universe is big, and Hayden’s about to invade it. Being drafted into a demon army wasn’t on Hayden’s bucket list. But when his soul is shoved into a human soldier on the eve of a new invasion, it’s not exactly like he can appeal the decision. Surrounding Hayden are demons, excited and ready. For them, the invasion promises a feast of souls and new growth. Their target? Berlis — a sword and sorcery realm straight out of classic fantasy. Hayden’s human status puts him at the bottom of the totem pole, meant to be cannon fodder that soaks up damage and dies first. But as he plunges into the carnage, he’s learning that he was born for the madness. Readers can expect: + Grimdark action and violence + Fighting, lots of it + Multiple worlds and magic systems + Slow burn