Arthur has a laid-back and worldly-seeming attitude, and shows disdain towards society's discrimination against the LGBT community and people of color. He is somewhat absentminded, either having forgotten or being unaware that one of the community's members had left for rehab.
Arthur is an older man with receding gray hair and a short gray beard. He wears an orange tie-dye shirt under a blue jacket with a yellow logo, gray shorts, and white socks with sandals. He has tattoos of a unicorn against roses on his right arm and a demon's head on the other, a dragon's silhouette on his right ankle, and piercings on both ears.
Arthur was closeted for most of his life, marrying a woman and having three daughters before summoning the courage to come out to his family around twenty years into his marriage. Arthur was disowned in response and alienated by his ex-wife and two of his daughters. Arthur had a "serious breakdown" alongside his boyfriend, Stanley, before leaving their homes in the San Francisco Bay Area.
At some point, the two were introduced to Away, where they settled down and decided to live their lives alongside the community of outsiders. They built one of the only houses in the community ten years prior to the events of the game from "ruins of their past lives." The only child Arthur remains in regular contact with is Becky, who visits him and Stanley at Away every now and then.
Episode Five - "Wolves"
Upon arriving back at Away, Sean Diaz must visit Arthur and Stanley outside their house to return their telescope. There, the three talk about Sean's experience sleeping in the canyon and their histories prior to finding Away. Afterwards, Daniel calls Sean and tells him he saw Arthur and Stanley kissing the other day, and can say that he "[hopes] somebody cares about [him] like that when [he gets] old." If Sean chose to take Daniel's treasure quest, he can unsuccessfully try to ask Arthur for a hint.
While preparing to leave Away, Sean can say farewell to Stanley and Arthur. After a short conversation, Arthur kisses Sean on the forehead before he leaves. Later, Arthur is present with the other members of Away as Sean and Daniel drive towards the border in Karen's truck.
- Becky - Becky is the only one of Arthur's daughters who still speaks with him. She occasionally visits him and Stanley at Away when she can, and enjoys stargazing with them. She has a partner that Arthur approves of, despite Stanley calling them a "posh newyorker".
- Stanley Petersen - Arthur and Stanley have been in a relationship for at least ten years. He shows genuine love towards Stanley and values his happiness with him over his loveless marriage in the past.
- Sean and Daniel Diaz - Arthur becomes attached to the brothers over the course of their stay at Away. As Sean says his goodbyes, Arthur can offer to hide them from the police and state that they will always have friends and a home with them.
- Unnamed ex-wife - Arthur has an unnamed ex-wife of 20 years who he divorced after coming out to his family. She was a fan of an unnamed medieval fantasy show, which Arthur notes to Stanley.
- "Speak for yourself, grandpa. My body might be 59, but I'm 25."
- — Arthur to Stanley in "Wolves"
- On Karen's grocery list, Arthur is listed as wanting Chock-O-Crisps, baking soda, and foot powder.
- Arthur enjoys eating candy provided by David Madsen from his trips to town, a fact which Stanley teases him for.
- Arthur dislikes Stanley's coffee.