Ryuusei Narukami, the former Demon King, just wants to spend his second life living in total peace as a lazy shut-in NEET. That quiet dream crumbles the moment he steps back into society as a high school teacher and runs straight into Meteor Hanaori, the legendary Hero who killed him, now attending his school as an ordinary teenager. Forced to navigate school administration while keeping his identity under wraps, Ryuusei faces a hilarious predicament: surviving daily encounters with his sworn enemy without letting his past ruin his new career. The Hero and Demon King's High School Reunion delivers a bright, energetic rom-com packed with chaotic banter and playful absurdity. It flips the classic fantasy rivalry on its head, swapping epic sword fights for classroom antics, awkward tension, and surprising romantic sparks. If you enjoy enemies-to-lovers stories, sharp comedic timing, and fun twists on traditional Isekai tropes, this lighthearted series is an easy recommendation for your watchlist.