The name given to a day when a man chooses spend all of or a significant part of the day with a group of girls/women instead of hanging out with his bros. The name Lady Day should only apply to those cases when the male actively seeks out said ladys and explicitly does not apply to cases in which sex is involved(e.g. man has stayed over and gets caught in the morning, man is actively pursuing sexual relations with one or more of the ladys)
Bro 1: Hey where did your roommate go? I thought we were going to the game.
Bro 2: I saw him next door having coffee and scones with a bunch of girls
Bro 1: Ohh, he must be having one of his Lady Days