Toasters, that’s what they jokingly call themselves
I am not sure how it works, maybe some nanomachine things like synths
I heard they are partially robotic
And some people made jokes on their reddit place about “untoastering” a protogen, those pictures made them look similar to a sergal
Without fur is another story
the torso can be how ever long, but I think the head looks a little weird… Protogens usually have more egg shaped heads but it’s your choice! that’s whats so great about art, you can do whatever you want with it. Also fursonas don’t really have limits so thats cool too. i guess.