At various points throughout Dedue’s life, he’s struggled with consistent nightmares and anxiety dreams. So he kind of dreads going to sleep and finds little tasks to justify staying up (usually “oh I can’t go to sleep until I know Dimitri is safe in his room,” because Dimitri also has chronic insomnia and does the same damn thing).

Typically, once Dedue is finally in his bed, he might do a tiny bit of sewing before sleep. Then he’ll ruminate over the events of the day and his various worries. As he drifts closer to sleep, he starts to allow himself to have some, hm, more steamy thoughts about Dimitri that he pushes to the back of his mind for most of the day. He feels bad about it though, but it does help him fall asleep.

This general pattern has been ongoing for maybe two years and did not change when he arrived on the ship.