Naisho No Kan-in - -manatsu No Asedaku Koubi-

After a quick search, I find out that "Naisho no Kan-in -Manatsu no Asedaku Koubi-" (秘密の観音 〜真夏の阿せダク公演〜) is a work by the same author as "Ore no Kanojo to Osananjii". The series is known for its harem-style, romantic comedy elements with some ecchi and fantasy aspects. The title translates roughly to "The Secret Bodhisattva - The Unfolding Performance of the Heatwave Summer-" or something similar.