Saiki Kusuo no Ψ Nan: Season 2, Episode 11

2 - 11: An Ugly Bolt Out of the Blue + Conceal Your Hidden Power! + A Fight Between the Two Worst People + A Miraculously Average Guy Appears! + Disaster in the Library Room

Riki Nendo gets a love letter from a freshman coed and Kusuo figures it's a prank, but he soon realizes she's serious. Nendo, being Nendo, wants to say no.