I think you should be more especific about this. When you say hentai, do you mean sexual poses...? It this is the case... most of the cons 'family oriented' i doubt that you could do a hentai pose without being banned XD
As for Ecchi... do you mean panty shots, or provocative poses?
Katara fire Nation outfit from Avatar: the last Airbender (100%-finished)
Kasane Teto from Vocaloid 2 (100%-finished)
Planned for 2010:
Ciel Phantomhive from Kuroshitsuji (tentative)
Echo from Pandora Hearts (tentative)
Agitha the Bug Princess from LoZ: Twilight Princess (0%-planned)