why does Mulder wear a ring in S5E3?

(i personally dont see this as a spoiler, i doubt it even is)

episode is Unusual Suspects, timestamp is about ~31:37; while its not such a big thing, its not really explained later on or before the ep.. while Yes the woman in the episode (Susanne) in the beginning episode says that Mulder was her ex boyfriend, even his FBI little information panel says he is single, so..? i believe this is the first time he wears one, and its on his left hand, ring finger, making me think its a promise ring..? its just a question that puzzles me, i doubt it is connected to something offset either/his personal life (now talking about David), he would have taken it off?

just a little thing that puzzles me, nothing else, i noticed it immediately during the (sadly funny) tweaking out scene of him, the little shine of the ring immediately caught my eye

also not going to put in the full pic, he looks so stupid in that scene, i genuinely feel bad i love u my little weewee

(i personally dont see this as a spoiler, i doubt it even is)

episode is Unusual Suspects, timestamp is about ~31:37; while its not such a big thing, its not really explained later on or before the ep.. while Yes the woman in the episode (Susanne) in the beginning episode says that Mulder was her ex boyfriend, even his FBI little information panel says he is single, so..? i believe this is the first time he wears one, and its on his left hand, ring finger, making me think its a promise ring..? its just a question that puzzles me, i doubt it is connected to something offset either/his personal life (now talking about David), he would have taken it off?

just a little thing that puzzles me, nothing else, i noticed it immediately during the (sadly funny) tweaking out scene of him, the little shine of the ring immediately caught my eye

also not going to put in the full pic, he looks so stupid in that scene, i genuinely feel bad i love u my little weewee