Haha.... san.... the phrase "disaster come from the mouth" suit him well..... also about sosinof..... u know, he might be a typical spoiled authority abuse kid but:
-the first encounter will and san did block the etrance i think it's reasonable of him to tell them off
-it seems he is on duty for opening the drom door that year... and i'm of the same mind as san in he's just trying to show off.... but honestly? I think it's cute for a brat to try show off his good point (being able to read the damn kanji) to his underclassman
-if he realy a noble who don't give a single damn about the commoner, how come he's able to recognize san as someone from his teritory? Maybe san had characteristic special to his teritory but if u realy don't care about the commoner, would u realy care their special characeristic? That or he looked up the student list or something trying to learn about his classmate and such? (But i think it's unlikely since he would then know will's full name)
Overall? Maybe sosinof just a tsundere lol.... maybe i'm also wrong mayve he's just a spoiled brat.... well then on to next chapter!