Happy cats make for less distractions
Puff and Yellow fin love sleeping on towels. Double win since towels are easy to throw into the washing machine and results in less cat hair in my place.
Cats seek safety in being together. I think they see me as the alpha cat and want to be near me for what they perceive as our mutual safety. A pride of cats will watch out for one another - spot predators while members of the pride sleep.