Rinne no Lagrange, Galilei Donna Recommendations
Rinne no Lagrange and Galilei Donna are science fiction theme series with a trio of girls as the main characters. Together they take on challenges ahead of them. One of these challenges includes the invasion of a mysterious force that threatens their very existence.
There bits of mystery involved around the series as to who these invaders are and their origins.
Both series contains action, comedy, and also some fan service.