Baren has black messy hair that is held in a ponytail which splits into two and usually curves upward and decorated with feathers. He wears long earrings and an eyepatch over his left eye--he has worn the eyepatch since he was a child. He also wears an kimono which is often worn loosely so you can see his chest which is wrapped in bandages along his abdomen. He also wears a haori with the with Kumo written on the back. He has two wrist bands and is often seen with an kiseru, which he also uses for fighting. He is considered rather attractive which in turn makes him very popular with women.
Baren overall is rather stubborn and holds grudges easily. Once he's made up his mind he's not likely to change it and if you try arguing with him he will probably tell you to shut up or says he doesn't care. He comes off as carefree and is rather straightforward with how he feels about things generally. He could hold a grudge against you for just simply being affiliated with someone he doesn't like. Baren also is pretty quick to anger Ishida Sakichi being an expert at it. There are several times where Sakichi says something and Baren lashes out at him telling him to shut up or that he's stupid. Both twins are also notably rather lazy. Baren is found yawning a lot and laying around at the shrine when there isn't much to do.
It is noted by Gengetsu that Baren is actually very good at taking care of people, which is most noticeably seen when he is with Okuni who says that Baren is also dependable and sensible, makes sure things are tidy, takes care of her things, and that he is very capable. Okuni also notes that Baren gets lonely rather easily, so he doesn't like being separated from her for very long. He is also cunning and sly, being able to work through problems with ease and even lead the Momochi through a war, expertly at that.
He is also referred to as being persistently annoying, loving to bug people and not shut up about it until Okuni shut him up by flattening him. Both the twins enjoy pranks, and Baren seems to be entertained by them rather easily and find pleasure in doing them over and over again. He is also really good at attacking people's nerves to get a reaction out of them. He is also skilled at provoking people in order to make them spill information, which he did with Oda Nobunaga's son.
When Okuni and Baren's mother, Asahi Kumo, was still alive, they had a surprisingly good relationship with the inhabitants of Oumi. But when their mother died, the villagers burned the shrine, blaming Asahi's death on them. The twins realized that they weren't the ones loved, but their mother was.
Since then, the sky clouded over, the villagers didn't trust one another anymore and started turning on each other. The twins couldn't stand to see them this way, so they used their reputation as the "children of misfortune" and turned the villagers fury towards themselves. The villagers smiles returned, but in return the twins became the most hated of all of Oumi.
To Ishida Sakichi: "We have always lived alone, just the two of us. No one has to understand us and we don't want them to.''
To Okuni Kumo: “We’re two but we’re one.”