Da lap or stomach of the "underneath"
partner in a couple during
intercourse, where the "upper" person is "
sitting" or "riding" on the lower one.
To avoid injury or distress to someone who's acting as a "love-seat", the "sitting" person should
consider (1) how sturdy his "seat" partner is, and (2) how big/bulky/heavy HE HIMSELF is, and therefore whether he might be excessively
squashing his
romantic partner.