Karen Joshua is a character who appears in the 1996 One Year War side story Mobile Suit Gundam: The 08th MS Team. She is an experienced mobile suit pilot.
She didn't trust Shiro at first; however, she never respects him. She underestimated him.
Later, Karen pilots an RX-79(G) Gundam Ground Type for most of the series, displaying proficiency with a multitude of weapon configurations, though usually outfitted with an NF·GMG-Type.37/100mm machine gun and later a P.B.R-0079/A12 S-000011 beam rifle. Because of damage done to her Gundam in Episode 9: Front Line (a Zeon MSM-04 Acguy severs its head), in the last couple of episodes her Gundam's head is replaced with the head from an RGM-79(G) GM Ground Type. This earns her the nickname "GM Head" with pilots outside of the 08th MS team for a brief time which she is annoyed by that nickname and thus bad karma for her because of her disrespect of Shiro.
At one point, during a time when Shiro Amada is under suspicion of being a Zeon spy the 08th MS Team is assigned a recon mission with a low survivability rating. The mission was also a test of Shiro's loyalties and Karen was given secret orders that should Shiro desert during battle she was to execute him, unaware that fellow team member Terry Sanders Jr. had been given similar orders. When Shiro proclaims that he is leaving the service so that he can deal with the Apsalus III his own way Karen acquired a weapons lock on his mobile suit and fires with her vulcan gun but intentionally misses Shiro's Ez8.
She deeply regretted betraying Shiro. She saw her-self as a bad soldier. She never got a chance to apologize and reconcile with Shiro.
Trivia
She is called GM Head.