Taken in sleep - DMing

Hi all,

My players are currently in a luxury hotel resort chilling from a war, but I very much have planned the hotel to not be a relaxing stay.

When they rest their heads for the night, I'd like to see if I can take them one by one in their sleep to a beast's lair.

Question:

• would passive perception be the marker here to see if they awake when they are taken?
• should they roll for perception (even though they're asleep? Sounds wrong?)
• do I have to roll the beast's sneak for each abduction and they appose with passive?
• would a constitution check be a better roll to appose if they're taken by a paralyzing poison?

Want to ensure I have some kind of solid mechanic for them all.

Many thanks in advance!