This might sound mean, but one of the members of your ships is overworking themselves/super stressed and refuses to sleep, so the other SO slips them some kind of sleep formula (IDK science) and they just have this small “How dare you” look before *thunk* passing out. SO: “(s)he is going to be so mad when (s)he wakes up” as they drag their SO to their room. Then they wake up and small argument before both just cuddle and sleep

ribbons-halos:

I can only see that with McSombra but even then, it would have to be a desire situation. Mabye if McCree or Sombra were terribly injured but refusing to stay down and rest, the other would slip them something. It would cost a little trust though, and time to rebuild it. 

McCree: For heaven’s sake, Sombra! Stop moving, you’re bleeding everywhere. 

Sombra: We have to *cough* keep moving.

Sombra: *eyes suddenly droop*

Sombra: *looks at the bottle before looking back at him*

Sombra: You sonuva…

Sombra: *passes out into his arms*

McCree: *picks her up bridal style*

McCree: *sighs* Sorry, darlin’, but I’m not watching you bleed out.