Otto is a human Polish man with short curly blonde hair and bushy blonde eyebrows.
According to the model sheets, he is 5 1/2 ft tall.
He wears a deep green sweater with white embroidery on it, light blue jeans, and brown lace-up work boots.
Otto was once a huge fan of Horsin' Around. In the present day, he remains a fan, although not to the degree he once was. This implies Otto likes BoJack more than the other dads while still being very protective of Hollyhock. He does not like Polish jokes.
He and the other dads sometimes communicate in a "Dad Speak" with the intention that people outside of the relationship (including Hollyhock) wouldn't be able to understand it.
However, unbeknownst to the dads, Hollyhock understands what they're saying perfectly well.
They live in Wichita, Kansas.
Otto and the other dads are mentioned numerous times throughout Season 4 by Hollyhock.
They make their first appearance in Lovin that cali lifestyle!!, when they travel to L.A. after Hollyhock accidentally overdoses on amphetamines (later found out to be caused by Beatrice putting weight loss supplements in Hollyhock's coffee).
The dads blame BoJack and refuse to let him see Hollyhock ever again.
In What Time Is It Right Now, BoJack travels to their home in Wichita, Kansas. After begging them to hear him out, he explains how he discovered he isn’t actually Hollyhock’s biological father—his father Butterscotch is.He also found out Hollyhock's mother is his family's former maid, Henrietta Platchkey, and he wanted to give Hollyhock her phone number.
They agree to tell her, but still tell BoJack to leave.
The dads seem to have allowed Hollyhock and BoJack to talk again, as Hollyhock and BoJack continue to have a distant sibling relationship afterward. Hollyhock even visits him in Ancient History.
In Intermediate Scene Study w/ BoJack Horseman, Hollyhock mentions three of her fathers were disappointed that she quit when she quit rugby, while the other five were relieved to hear she quit the team it is not specified which of the fathers were disappointed and which were relieved.
- The Language (or "Dads Speak") of Hollyhock's fathers actually consists of adding "ittag" after every first letter in a word (i.e. "What do you guys think?", becomes "wittaghat dittago yittagou gittaguys tittaghink?") the language also doesn't seem to use the word "Is."
- Otto is the one that Hollyhock is messaging when she faints at the beginning of lovin that cali lifestyle!!.