Music, reading, some mobile games that don't ask for large portions of time but also aren't super predatory pay to win games, taking a quick break to watch 1 episode of a comfort show, eating (can be done alongside any of the others), or if you want to feel productive while taking a break, maybe...
I do wonder if slimes taste like jello, but they probably don't have any taste. Most of the stronger creatures would probably be too tough.
So fish is the way to go. Probably a leviathan or a hydra.
As an American who has access to mostly safe meats, I'm legally obligated to say medium rare (for beef only, everything else I prefer well done. Especially pork.)
Crosscode (game) has the main character permanently in the game and side characters not always logged in, granted it's probably not exactly what you're going for.
"Even if I was given a chance, I wouldn't undo this. I couldn't just go back and pretend this never happened, that I never lived through the consequences of this choice."
Just like last time, this is in no particular order:
1. Shiraori, so I'm a spider so what
2. Thorfin, Vinland saga
3. lelouche, code geass
4. shigeo kageyama, mob psycho 100
5. fushi, to your eternity