Space Pirate Mito.

Most teenage boys have enough trouble just dealing with the pressures of school and dating, but 15-year-old Aoi Mitsukuni's life becomes exponentially more complicated when his mom returns from a long "business trip." He discovers that not only is his beautiful mother actually an alien, but she's the notorious Space Pirate Mito to boot! To make matters worse, the girl Aoi likes at school is actually a secret Galactic Patrol agent attempting to find and arrest his mother. No one ever said being a teenager in love was easy!