Two of my three cats would sleep on the bed if allowed, if the bedroom door is accidentally left open at night then they creep in and sleep on the end of the bed, but I try to keep them out as much as possible. Not necessarily for hygeine reasons, more that they're just plain annoying; Jez has a habit of sleeping right next to your head and purring like a motorbike in your ear at 3am or nibbling your ear lobes, elbows, fingers or anything else that might be sticking out of the quilt, and Raff likes toe chasing and nibbling throughout the night. Usually they sleep outside the bedroom door, and all three sit in a triangle waiting for me to get up and give them their breakfast :-)