Sharon Heim is a supporting character appearing in all versions of Muv-Luv Alternative: Total Eclipse. A 2nd Lieutenant of the Infinities Test Flight, Sharon's easy-going attitude hides her sharp wit and piloting skills.
One of Yuuya Bridges's long-time comrades, Sharon served in the same test flight as him, along with Leon Kuze and Ghost Flight team leader Rick Sven. While she got along well enough with Yuuya to be his lover, Rick's death caused a falling-out in-between Yuuya and Leon, and Yuuya was later transferred to the Yukon base partially as a result of the incident. While Yuuya and Sharon broke up, her relationships with others who were close to Yuuya, such as Vincent Lowell, remained amiable, and she did not bear any ill feelings towards Yuuya.
Sometime later, Sharon was assigned to the Infinities, with the callsign of Infinity-4. She and Yuuya met again when the Infinities were ordered to participate in Project PROMINENCE at Yukon Base, this time with Sharon being Leon's lover. While out in the city with Leon, she soon met Vincent, and spoke to him about Yuuya, looking to find out more about his current life.
A few days later, Sharon, accompanied by Leon, would also meet with Yuuya, who was accompanied by Takamura Yui. The women's conversation was cut short, however, when Leon and Yuuya started to exchange blows with each other, leading to the four having to run from UN MPs sent from Yukon Base to defuse the situation.
As a member of the Infinities, Sharon would participate in all of their Blue Flag battles, and their subsequent covert mission into Soviet territory during the events of the Yukon Base Incident. After returning from the north, Leon and her managed to meet up with Takamura Yui and Yuuya on the field of battle, allowing them to focus on the BETA, as well as helping them to clear Christopher's forces from the area.
- One of her more well-known fan nicknames is BEEG AMERICAN TITTIES.