Since we are talking about Masamune, I did a quick google search.
https://www.youtube.com/channel/UCLJBAVHSkvgvo-MKHZ_uvsg pretty sure that is his youtube account. Lots of Overwatch and 21Pilots related likes.
There is also a private Twitter account: https://twitter.com/MasamuneSato It's real name seems to be "Carlton Washburn", but without any more details it's hard to say if it's really the same guy.
There are some other accounts using the same name that could be his (on e.g. pinterest), but I don't see a lot there.