Three great words, made even better when put together. Which is kind of the premise of the fornication in La Blue Girl: Initiation — put everything in everywhere. This, of course, is made possible due to all the tentacles. Tentacles which insert themselves everywhere.
Our heroine, Miko Mido, said supernatural sex ninja, is penetrated in every orifice by the demon’s tentacles — there’s even tentacle tit fucking. You can watch some of it here, in this dual review of La Blue Girl. (Click on the first pic in the article to see the hentai clip.)