Marika Neagle was a Warlord with flying special in service to Faq, who worked with Jillian.IPTSF Text 28 She was killed in action during one of Jillian's mercenary mission - over a hundred turns before the events described in 'Inner Peace'. Jillian regretted losing Marika as they made an excellent fighting team.
It is implied that Jillian and Marina were romantically involved.
Real World References
Her name is probably a pun on 'American Eagle'. Whether this is a reference to the American Airlines' American Eagle brand or to the American Eagle Outfitters is unknown. This may just be a simple reference as Marika Neagle is known to be a flying unit.