Taruby's two newest Chapters of Okitsune-sama (25-26)
http://www.savefile.com/files/1449324 have DTG as the love interest of main character Moji Shimeta is granted power similer to Youko by a "evil version" of the fox spirit that allows Moji into Youko, now Yuuko (the love interest) turns into the Evil Queen Pomera when ever Youko appears. The second chapter inclueds Evil conversion (or rather enslavement since the convert was already a evil mad scientist).
The rest of the series is good to but it's just guy to Kitsumimi.