KissXSis (2010)

S1E3 Alluring Sweets

Keita grows frustrated with Ako and Riko's constant kissing, prompting him to declare a no-kissing rule. Learning that Keita enjoys sweets, Riko attempts to make him some chocolate but ends up creating a disaster. After stumbling upon one of her father's adult DVDs, she offers Keita chocolate lipstick and convinces him to taste it from her lips. Just as things start to heat up, Ako barges in and ruins the moment by smashing the lipstick. Riko then presents Keita with another chocolate lipstick, but it turns out to be made from the terrible-tasting concoction she initially created.