Difficult question. They are not so much.
Visual Novell - Kawakaburi no cherry, Dekachin Kozou, Iyashinbo The Motion, Mama Shibori 3.
Flash games - "Meet and fuck" series have lot's of it, Maman Chun-li by システム4-5-1.
Anime - Aneki: my sweet elder sister (episode 2 especially), Milk Junkies...