Two short chibi character specials included in both volumes of Tennis no Ouji-sama OVA ANOTHER STORY: Kako to Mirai no Message. 

The specials feature the Oshitari cousins in a Manzai (&#28459;&#25165;) setup [a style of stand-up comedy in Japan, which usually involves two performers&mdash;a straight man (tsukkomi) and a funny man (boke)]. 

"Aruhi no Oshitari" involves Oshitari Yuushi who is tired of being the tsukkomi and wants to try his hand at being a boke but with disastrous results. 

"Aruhi no Oshitari 2" is about Oshitari Kenya in the role of a boke whose jokes didn't get through to the audience in a joint comedy show with Seigaku and Shitenhouji.

Tennis no Ouji-sama OVA ANOTHER STORY: Kako to Mirai no Message Specials