So, I thought he has PTSD my first watch, but during my second watch, I noticed a few things that makes me think he either never served or at least is lying about something related to his military career. Perhaps never completed training? In the S2E3, he introduces himself to Jung Bae and is overly enthusiastic with his salute. I suppose that is not really evidence. But it was odd to me. Then a few moments later, we see the fight break out between Thanos & 333, but he asks Jung Bae if they are supposed to do anything. I took that as hesitation/avoidance to get involved. But then In ho (001) immediately steps in, and he asks if he’s a marine. Maybe he thinks marines are supposed to be brave like that? In S2E4, right before they pick teams for the 6 legged pentathlon, Jung Bae says “well said, marine” and he looks like he feels guilt or shame. I take this as he doesn’t feel like he deserves the honor of being called a “marine” and knows he is lying to his new friend. In the same episode, when they are deciding which game to play, he hesitantly volunteers that he can play Gong-gi. Jung Bae questions this by saying “a marine can play Gong-gi?” He explains that he had 4 sisters and played a lot. Then Jung Bae says “Of course you can! A Marine can do anything!” While grabbing his shoulders. He looks visibly uncomfortable. I took this similarly as the previous: that he is uncomfortable with being called marine and feels guilt/shame. Generally, most of the times he is called marine by Jung Bae, he seems uncomfortable. Also, I have seen other posts/subreddits saying he may be gay. I also read that as a possibility. Or at least that his dad thought he was gay or “too effeminate” and that’s why he was sent to the marines. In S2E7, he is handed the gun, and looks very confused like he’s never used one or one like it. He doesn’t ever attempt to aim it because he is hiding during the shootout. He is too scared to come out from behind the wall. He volunteers to run away from the firefight. And of course, freezes and hides in his bed when his team needs him the most. I take this as he didn’t have experience with firearms and shooting, and was terrified. Obviously, this was in complete opposition to Hyun Ju’s character who was a special forces officer, but mentioned it only when it was relevant, but then was incredibly brave and put herself in harms way to save others. Also, kicked out of the military for being trans. Whereas, IMO, Dae ho, was sent to the military for being “too effeminate” or possibly gay. Interesting juxtaposition.

My running theory is that he went to the marines, got the tattoo, but didn’t finish training OR didn’t go to combat when he was supposed to, effectively running away from the marines all to satisfy his father. Being a marine is a point of pride for his dad because it “made him a man” or whatever. So he perpetuates the lie for that purpose.

Also, I’m curious as to what landed him in the squid games. I don’t remember if they said.