The pairing of the characters Suigetsu and Karin from the manga Naruto and the anime Naruto Shippuden. The name SuiKa comes from the first parts of the characters' names, and suika is a Japanese word for watermelon, so some have dubbed the pairing "watermelon love."
Person A: SasuKarin is better than your OTP!
Person B: No way, SuiKa is good for your skin!! xD