I can honestly picture Yamamoto bringing drinks/snacks for Shinjiro in that case, because 'YO MAN have you even eaten anything what are you doing not being social you're gonna end up not having fun that way :C' And he'll probably make a point to purposely go up to him and just chitchat a bit so he's not completely alone all the time.

AND IT IIIIS. His persona is probably going to be much of the same, honestly. :> Like Sif from Dark Souls but as an Akita with wings more or less.