On the surface, Viet looks like a nice guy, but he actually has a scary side.
I'm married to a man who is an angel outside and a devil at home, and we bought an older home that has a fine exterior, but the interior is worn out, so I'm having a tough time right now.
You shouldn’t be fooled by his outward appearance. I hated my instructor because he showed his superiors a nice face while he bullied subordinates, including me, behind their backs.
The outside face to something is the exterior of that thing.
This is a jukugo word, which usually means on'yomi readings from the kanji. This reading is usually for building exteriors and outside surfaces. The other reading そとづら is used when a person's personality comes to the surface and is a bit of an exception, so you'll probably see it less often. Just keep those differences in mind!