@Nk9bjP4A
The bed frames are about as thick as 2×4s. So if you push the two beds together there will not only be a 4in. gap between the two mattresses, there is also a hard wooden frame right where they would be cuddling once the destraction is out of the house. Also there is no reason to have seprate beds if you're just going to push them together anyway.
As for the leaving part, it was mostly because Red thought his sister and Aries were a couple. Gideon had been falling behind the other members of the hero's party for a while and was already feeling like he was holding them back. Aries prayed upon that insecurity and kepted harping on it till Red finally gave in. Him seeing Aries hugging his sister shortly after was the final straw that broke his will to resist and left.
@BrunoVilla
At first they stopped because the are both very experienced fighters living in a fantasy world. Ignoring sounds like that even in their own homes could mean a monster or an assassin would have a chance to sneak up on them. Second they didnt continue after identifying the noise as the kid because it would be even more awkward the next day. Granted the first reason conflicts with the second, but when you throw in Japanese often ridged morals on decency, you get scenes like this.