According to the official website, an OVA of Asobi ni Iku yo!
was announced to be released in March 2011. Asoiku characters will play a "certain game" to win a prize. A PR staff of Pony Canyon called it "an undressing OVA", with everything uncovered.
Sources: Asoiku official website
, ecoloji's tweet
Update on March 16th
According the official website, the March 16th release of the Asobi ni Ikuyo! OVA Special has been delayed to May 18th.
Source: official website