Injuu Seisen: Twin Angels

Both can be hailed as tentacle hentai classics. La Blue Girl is more on the fantasy side of things with weirder monsters, magic, and things like that with actually quite a focus on comedy. Twin Angels takes itself a little more seriously and has a similar setup with demons and magic, but dishes out the comedy for a little more action and violence. If you're in the mood for some older tentacle hentai, these are both worth checking out.