I wanted to post this drawing to explain two of the principals headcanons I have for Skwisgaar so I'll explain them here. Excuse my broken English, it not my first language. ;;
In my opinion he's the second youngest, the first is Toki.
So with this being said, I like to imagine that he was still very young when he started to join all the bands he mention on SnB episode and I personally think it was a way to scape from his home and his mother apart for learn more of the guitar and the music world. He was very skilled at this moment bc of all the time attached to play the guitar since he found it so that's the way he manage to enter in various bands.
But the thing about all this is that he was very young and in the majority of the bands the bandmates were people way more older than him and they didn't take Skwisgaar very seriously it was more like the mascot than an actual member so this occasion many maltreatment to his person. That's why he makes the disgust face when remembering his ex bandmates and how they want to hang from his fame now.
So that's my hc, I have some more but it costs me to explain it with my bad english but tell me what you think about it! I have some more hcs for the others characters so maybe later I'll post more of my hcs hehe.













