Bat-Cow

Bat-Cow is a comics only character who debuted in Teen Titans Go! #45 "Misadventures in Babysitting".

Comics
Bat-Cow was originally a cow that was found by Robin (Damian Wayne) during an investigation on a slaughterhouse, which the cow was sent to. Damian wanted to keep the cow and named it Bat-Cow. Batman decided they would keep the cow. During a later investigation, Batman discovered it had mind-controlling radiation inside of it, leading him to attempt to get rid of the cow. Damian, however would not allow him to hurt the cow.

After the events of Robin's death, Bat-Cow and Damian's dog felt a great loss in morale. Alfred Pennyworth and Nightwing had to take care of the cow. Later after Nightwing's disappearance, Alfred was the only caretaker of Bat-Cow.

Bat-Cow, complete with cape, spent time on a Wayne Enterprises-owned dairy farm. It was there the cow encountered the cosmic-powered "Forever People." One of them seemed to gain guidance from Bat-Cow's actions, namely when Bat-Cow gave one of the Forever People a scarecrow's hat.

Teen Titans Go!
Bat-Cow first appeared in the Teen Titans Go! universe in issue #45 of the comic line. When Superman got turned accidentally into a baby, he was sent to the Titans to babysit. When Superman got hungry, Bat-Cow was used to produce milk for him to drink but got tired due to Superman's heavy amount of milk.