bad eye
To bad eye something is to stare at it with great interest. To scope it out, look it over closely, check it out.
She's a really classy looking lady. Yeah,tell me about it.I was really putting the bad eye on her.
Bad Time Eye (Sans)
A blue eye that that Sans unleashes as some sort of last resort when he has a hard time defeating Frisk in the genocide route (uncanonically the eye is some sort of blue fireball)
Shoot! Sans used his Bad Time Eye (Sans) on us, Frank!