Fo Sho
- Same type of circle pattern inside eyes.
- Shit eating grin!
- The black eyeparts of the mask resemble Sho's 'makeup' under his eyes.
No Sho
- Missing the scar.
- Hair matches Chairy Potter, rather than Sho.
My theory is that Chairy Potter is actually Sho, adapting to ordinary life. However, he finally realizes that life sucks, and he's a slave to society and wants emancipation. So how does Sho react to this? Puts on a mask, and finally lets loose his crazy side and murders shadows for fun.
The motif of P5 pretty much looks like split personalities/masquerading. So perhaps Chairy Potter is just putting on an act, pretending to be shy and nerdy, but he's actually a crazy ass kid at night? The hair and the missing scar are the huge points that its possibly not Sho, but I think those similarities to Sho are rather strange unless Atlus are just being trolls.