Note: This character was a part of a dream and is not real.
Harper is BoJack and Charlotte's daughter during a drug induced dream BoJack has in "Downer Ending".
She is a horse with tan fur and a blonde mane, along with yellow freckles on her cheeks. She also has pale yellow fur on her mouth and a white diamond like shaped marking in between her eyes. As a baby she wears a purple onesie. While swimming as a child she wears a purple swimsuit with a green skirt and an orange carrot pattern. While swimming as a teenager she wears a purple, blue, and green swimsuit.
In BoJack's dream, he imagines a life where he goes with Charlotte to Maine instead of staying in Hollywood to become famous. In the beginning of this sequence BoJack is outside their cabin (which was from a photo Herb showed BoJack of Charlotte standing in front of a cabin, supposedly in Maine) chopping wood. Charlotte, his wife, calls him inside for dinner. After the two kiss BoJack asks if they could just stay this way forever. Charlotte then tells BoJack she's pregnant, to which BoJack reacts positively to. The two kiss. Winter becomes Summer, and BoJack now has a baby horse daughter named Harper. He is shown being a very loving and playful father with her. She soon becomes a teenager with a human boyfriend. They play in the pond in front of her home as an old BoJack and Charlotte watch them. BoJack asks Charlotte what she's thinking about. Charlotte responds "Oh, just how nice it could have been if you had chosen this life." BoJack then wakes up from his dream