From MangaHelpers:

On one normal day coming home from school, Bonta finds a cute maid waiting for him at his apartment, or so he thought. Turns out, she's actually a highly trained bodyguard sent in by his parent's family. Even though she's a bodyguard, she really wants to be a maid, so she stole the outfit of the actual maid that was supposed to join her in protecting/serving Bonta. Bonta now has the privilege/task of living with these two girls in a comedic triangular relationship. [DrCoke]

The volume also contains 2 oneshot sequels to stories from Megane na Kanojo.