Well that depends on the prey, and also how hungry I am, or if I'm in A Mood or not obviously

• Generally the case is I drop 'em, feed off 'em, then leave 'em to wake up by themselves being a little confused about the night, possibly even questioning if it happened
• If I've deemed them fairly worthless overall, then there won't be an "after" because they'll have been completely drained. Admittedly if I'm really hungry I accidentally do that, oops!
• If I kinda like them 'em, or like the taste of their blood at least, I'll probably add in a suggestion to just regularly leave a window open with no memory of why I should. Occasionally spending a bit longer with them, in trance or not, what's a little extra vampire time except a rare privilege for a mortal who isn't enthralled?
• Sometimes if I just need an extra body around then they're probably not gonna be woken up any time soon and remain a thrall to serve whatever whims I have. Maybe sometimes I'll briefly take them out of trance to watch their confusion before dropping them back down under their vampire's command~

But maybe, maybe, I'll be a little nicer~ Perhaps I'll turn a mortal I like, for just a night or so for them to get a taste for blood~ Wouldn't that be a real treat?