A long time ago in this bat's history, another flying creature discovered her. Those familiar know the creature by name. Clockwork... The metal Eurasian Eagle Owl fueled by rage, jealousy, and hatred.

He caught her and corrupted her mind, forcing her to serve under his command. She worshipped him like a deity, coming to learn that she was one out of many other followers. The evil was poisoning her mind, twisting her until she mentally snapped. She gave herself over to the demonic forces inside her, indulging the evil inside her by cleansing with hellish fire.

Her master has fallen. All of his followers carry a piece of him inside. The Hellbat above is hunting the other followers, draining their essence in order to collect all the individual parts. Only through combining all of the pieces can she resurrect her master.

How does that sound~? I needed something to visualize for this Bat. She's an important character. Thanks so much~

That sounds pretty cool and ties in with the story of the other character! An arch nemesis.

A true antagonist and rival matches the hero in physical capability.
The personalities will differ; their morals and goals always creating conflict between the two that conversation can not resolve.