The King of Gensoukyo Touhou doujin series has a few MC scenes not really EC but it had potential. The first few are non-h with some ecchi cope-a-feel moments. There are two exclusively hentai ones, one featuring Sanae and one of the middle ones with Reimu, Yukari, and Marisa is hentai though they don't seem to have the MC thrown in.
Both Reimu and Aya are defeated and then controlled by a super-powered Rinnosuke Morichika. Brief but fun.
Here's the list by the author:
http://g.e-hentai.org/tag/yudokuya
The order:
The Before Chapter
The Middle Chapter (MC)
[Yudokuya] gensou sato no ou kouhen (touhou)(C75) (MC)