pippinleaf That is quite odd (the pants thing), and not at all what the op is asking! As far as we know, there is nothing like that going on!
OP, I don't know about your stbex, but my dh hasn't had a 'wet dream' as long as we have been together. And yes, he obviously gets an erection sometimes, but has managed, to date, not to molest our 6yr old who regularly shares our bed.
It really is odd that you think wet dreams + erection = child abuser.
I am sorry, op but I have to join the ranks of the confused here. You have always had pillows between them because you don't like bodily contact between them. Now your daughter is 7 this will be hugely confusing for her, that she isn't allowed to touch her father, even in an innocent cuddle way, while sleeping.
You now don't like them sharing a bed. The reason for this constantly changing throughout this thread, starting at wet dreams & erections, then because he is doing it as emotional blackmail, & now because he is smelly & drunk.
He is leaving your house as you are separating, it isn't a huge leap to think he will miss his daughter. If I was leaving my children for any reason, I think I might be inclined to snuggle with them now & again.
To be honest, I don't think YOU know why you don't like this, and you are clutching at straws in order to justify why you find it unacceptable.
My dd is 11 now & a few years ago we all (me, dh & her) had a huge talk as to why she didn't like her father (or me, come to that) tickling her. Completely normal behaviour that we have had since she was able to play, but now she was growing up, she didn't like it as her body was changing. Dh hadn't realised & he stopped straight away. Kids DO grow out of wanting to be played with, it isn't any sinister on my dhs side that he didn't realise why she didn't like it anymore, nor did it suggest he was being inappropriate. he still forgets now & then (like twice in 6mths) but she stays stop & he does. I don't think that is dodgy, or wrong...he just forgets that she isn't his 'little' girl and that he needs to respond to her in a different way now.