Foes is the adopted child of an elf and a gnome whom he refers to as his mom and ren. Foes has told the party his name ("Foes") is short for "potato". He started to explain it was because he looked like a potato and they found him on the ground, but then cut himself off and said it wasn't important.
His mother was Pip Jewelhand and his Ren was Miradan Ruinseeker. His parents owned a toy and curio shop where they took in likely illegal goods from the ruins of Asuvia to study. They died due to an accident involving a puzzle box which Foes owned prior to it being taken by the entity first encountered inside the geometry tower. While he was present, he's stated he doesn't remember what happened beyond a flash of light.
Childhood
He's mentioned that his parents found him in a bush, since clarifying it was likely his grandfather who placed him there in order to surprise his Ren as that is how his grandfather found them when they were a teenager.
It is known his ren was the one who taught Foes to sew.
In his vision in the foxhole, Foes was shown as a young child some months before his parents' deaths. The familial relationship was strong. Pip referred to Luceran as "Da" and Foes was often called "Glim", their Ren being called "Glimmer" by Luceran. Miradan was called "forgetful" with Pip writing and categorizing all their journeys. Given the vast number of notebooks, it can be summarized the two had done a lot of travelling prior to settling down.
Luceran, Pip and Miradan discussed the puzzle box. They stated Foes had found it in an old box when the workshop had been left unlocked, subsequently "falling in love" with it.
Luceran was able to quickly solve it within minutes, something which took Foes years to do as a child. He stated it had an uncomfortable familiarity about it, but didn't specify further. As the conversation moved on, they discussed how safely Miradan and Pip were keeping Foes as well as how Foes needed to stay quiet to authorities about his parents' ongoing illegal activities.
There were blueprints and pieces within his parents’ possession which were similar to the constructs which attacked the party and juniors in Ira's Mirror.
Immediately after his parents’ deaths, Foes was found outside the family home in a coma. While nothing appeared to be wrong with him, he didn’t wake for several days.
Whatever his grandparents found inside the home confirmed his parents’ deaths, but they have not relayed this information to Foes. Luceran took possession of most of the belongings left inside—likely without the permission or knowledge of the Jewelhands—and the rest went to Foes. The home was destroyed at the behest of the Jewelhands only days after the accident occurred. As far as Foes is aware the lot is still owned by the Jewelhands and left intentionally empty in the sprawling city.
Adolescence
Sometime around age 15, Foes lost most of his left hand and most of the hearing in his left ear.
During his childhood and well into young adult years, Foes was never around many other people his age.
During his teenage years, he spent some time with a gnome-tiefling named Hana. As Foes was generally disliked and bullied by his peers, Hana often pretended not to know him. This led Foes to associate spending money on Hana in exchange for time spent with "an acquaintance" who he has stated he cares for. He also developed hang-ups around friendships due to the constant bullying.
The party has seen a vision of Foes as a teenager attempting to confess to a gnome. He was rejected viciously. Seeking any comfort from Hana also ended in rejection. Foes left to find somewhere to cry.
Adulthood
Foes met Hiss around 10 years prior to the start of the campaign. They formed a close relationship to which Foes has described as a "sex friend".
Sometime around 4133, he scuffled with Yu Huang. A memory from the tower in the lake showed the two of them talking. Yu Huang held something in their hands, talking excitedly. Foes looked exceedingly bored and didn't seem to be paying attention. Foes remarked he hadn't, "been very kind" to Huang in that moment. Despite the little impact on the actor, the fight left Foes with deep feelings of shame and inadequacy.
When he turned 56, he decided on a whim to travel to Liming to pursue magitech seriously. With his grandparents threatening to disinherit him, he had no money to leave Su-an Toan. Somehow he managed to leave anyway.
A memory in the tower in the lake showed Foes on an airship with an air genasi with blue skin and cloudlike hair, named Hiss. They stood close together, leaning over the railing. It can be assumed this was from his trip to Límíng City.
From there, Foes arrived in Límíng City.
Family
Foes was raised by his grandparents, Yosmin and Loryn Jewelhand with some involvement from his grandfather, Luceran. His parents died in what seems to have been an accident when he was very young. Foes has since stated the accident involved the puzzle box he's been seen carrying around.
His grandfather is supposedly a herbalist who wanders "somewhere to the north". His grandparents appear to own high-end jewelry and trinket shops as well as work as artisans.
His grandparents are known to be overprotective in an attempt to keep Foes safe so they do not "lose [him] like they lost [his] parents". Foes has also said there was a third grandparent who died in Su-an Toan's civil war long before he was born.
Luceran stays in touch via letters. He's said his grandfather would play the "quiet game" with him and give him candy if he won. Based on a vision showing Luceran and Foes talking, Luceran continued visiting even when he was barred from doing so. The two of them seem to be on very good terms with one another, hugging and chatting.
Relationships
Hiss
Foes has described their relationship as "friends" and stated it is intimate in nature. While at the boardwalk with the party, the two did appear to be on a date. They held hands, cuddled, and kissed frequently.
It's clear Foes cares about them and their opinion greatly.
He has stated Hiss has called landlords "leeches", indicating that he wasn't surprised to hear about the pitfalls in renting due to this opinion.
Hana
Hana is a childhood "acquaintance" who didn't appear to be very kind to Foes when they were teenagers. It's unclear how their relationship may have changed into adulthood, but Foes has stated he cares greatly about her. In a vision with his grandfather, Luceran referred to her as a "friend". Foes mentioned to him they were writing letters to one another.
She was the one who brought Foes to the job at the Serpent Gardens as well as giving him housing when he first arrived in Liming.
Mai
Foes owns a blood python named "Mai". He's said he's owned her since he was young and that she isn't very bothersome.
Given his aversion to killing rats for his moss, he was likely able to find already deceased food for her.
Fakir
Foes likes Fakir. He's said Fakir is always honest and kind to the party, and that he has some amount of admiration for that. Anytime anyone is rude to Fakir about being part of the Jihui Sect, Foes's streak for cruelty readily rears its head.
Niraj
While Foes is able to acknowledge the others' distaste for the man, Foes doesn't seem to be too deterred. He'd expressed some attraction until hearing about his engagement to Yu Huang.
Palavi
Foes likes Palavi, considering her to be an interesting person. He feels genuinely guilty over stealing her design, but plans to stay in touch with her.
Danilo
Danilo was met at the Crystal Star Casino while the party was doing a recon mission there. While under a disguise, Foes became charmed by Danilo who he mistakenly believed to be quite wealthy (a possible contact for the strange happenings in the casino). The two then subsequently spent the night together, with plans to go on a further date later in the week.