Kanojo ga Nekomimi ni Kigaetara, When My Girlfriend Put on Cat Ears, 彼女がネコミミに着替えたら그녀가 네코미미로 갈아입으면 Cat Play Punishment
Based on the adult manga by Miyabi.
A guy wins a bet against his girlfriend and now she has to do whatever he says. He wants her to dress up as a cat, film a sex tape and fuck her out in public. You know, standard stuff.