Who has the energy to wake up in the mornings?
The two of you were always a tangled mess of limbs in the morning, Mercury especially couldn't seem to keep to his side of the bed. His arm was thrown across your chest as he laid on his side, his one leg nudged up against yours as if to remind you that he's still right there. His mouth was always slightly open, with you occasionally being unlucky enough to get his drool on you (sometimes, if luck was on your side, it would just be on his pillow).
You're generally the first to attempt to move out of bed, which quickly awakens Mercury, who's sensitive to all types of movements due to his nature as an assassin. He would quickly case the room for danger and when he noticed it was only you trying to get out of bed, he'd groan and grab onto whatever body part of yours was closest.
"It's cold now."
"I'm sorry but we have things to do today."
"That can wait until later... Probably."
"Probably not."
There was a variation of this argument every morning, Mercury in deep denial about who your boss was and how she'd react should the two of you not complete what she wanted in a timely manner. He'd then realize that even if he didn't give a shit, you might get hurt because of him, and begrudgingly joins you in the land of the living.
"I wish I was asleep." He would mutter as he passed you by, and you would simply smile, kiss his cheek, and agree that being in bed with him was much better than whatever was on your plates for the day.