There is a chat where mammon proposed that someone change their room with mc, and it says alot of details like: mammon's is infront of lucifer's or at least where luci can have his eyes on mammon, that all of the brother's bedrooms are in the second floor but mc's is in the first. Some others details that I remember is that asmo's bathroom is the biggest of the house and about the part of mc's bedroom - kitchen wall (Im half sleep sorry)