Dash! Kappei

Kappei is a dramatically short guy but he is a master in every sport. He lives as a guest in sweet Akane's house, and he's in love with her, but there's a strange rival, her dog Salomone (Italian name) who plans evil traps to encumber Kappei. But the dog has also another function: he explains all sport rules when a new sport is depicted. Kappei is fond of white female underwear, always trying to lift girl's skirts up.

(Source: Anime News Network)