The Shroob Queen

The Shroob Queen (or Elder Princess Shroob in the North American version of Mario & Luigi: Partners in Time) is the Queen among Shroobs, older Twin Sister of the Shroob Princess and the Main antagonist of the Game.

Before the "Cobalt Star" event. ..
There was an invasion going on in Planet Neko and must've killed Tobias's wife and shroobified his soul somehow.

After her Defeat in the Cobalt Star Event. ..
She along with the rest of the shroobs were held prisoner in Bowser's Castle Frozened somehow in Mario & Luigi: Bowser's Inside Story. ..