Question about the, Oasis i think is what you'd call it after you beat the kung fu guy. Is there anything to do there other than drain yourself if you went and messed with the weird plant thing to the left of the bed?
Also is the futa boss still just plot and you have to let her beat you to progress?
You really could have edited your original post to avoid double posting, Dude.
Anyway, the answer to your first question is no. You go to the plant thing to refill your hunger and the "Oasis" place is used simply to drain the excess. At least that's what it's for if I'm remembering correctly.
And no. You can't beat the futa boss
yet. I am fairly certain this will be the branching point when Eluku decides to make his guro route.
The futa boss does have two loss scenes though. There is one for getting the crap beat out of you and then there is another for being fucked into submission. Just in case you didn't know.