Shirohime

Shirohime is a white white horse that was raised to become Yotaro's steed. She is usually seen with Alice; although, there are instances that show her in a human form and being able to talk like in episode 1 with Alice, however, it is not confirmed as to whether it really has a human form or the ability to talk (more-so on the ability to talk). However, it is shown that it can understand human language.