This interaction between Enjin and Amo is so interesting with how hard it's to make sense of but it reveals so much about Enjin and even Riyo.
And it starts right after Amo appears for the first time.
Enjin and Riyo immediately see that something is going on with Amo. It's hard to tell what they talk about but they very well could've understood that Amo is a victim of human trafficking and sex slavery. The reason why those two specifically would have that conversation is probably because something similar happened in their shared backstory, as in, the part of Riyo's backstory where Enjin came and pulled her out of the assassin lifestyle she lived until then. Riyo might've known girls like Amo and Enjin might've met them as well.
How they were able to tell what Amo's story is might be by recognising her white and orange scarf. She didn't have that when she was younger and it's similar in pattern to what the trafficker wears. In the world of Gachiakuta, this scarf might signal slavery of some kind.
Then comes the actual interaction between Amo and Enjin. What makes their conversation with her go sideways is Enjin putting their talk on a scale: we give, you give, which shatters the fragile goodwill Amo had for them. What's interesting here, is that Enjin was uncomfortable talking about love and crushes with Amo which he openly says.
When Amo had her first crashout because Enjin made their talk a transaction, Enjin pivoted and told her the opposite saying he liked her hoping to calm her down but it only prolonged her agitated state. (Note that Amo takes great offence at someone faking love for her which fits with her twisted understanding of it. The creep part wasn't in the anime.)
When that also failed, Enjin decided that he couldn't make this worse and so he told Amo his mind which is that she should cover up more because it's difficult for him not to look at her body. Which of course made things worse again.
The way this conversation devolved can be explained by Enjin being uncomfortable when younger and older girls dress like Amo. This could be because he does find an outward appearance like that sexually appealing but he doesn't want to see it on girls. It could also be because he would assume that a girl like her wouldn't dress like that voluntarily, meaning he sees signs of grooming on her if not in the beginning than now at least.
Telling Amo to cover up is either a paternalistic "men will find you attractive, don't do that" situation or it's a bad attempt at correcting the influence of a potential groomer in the background. It could also be a mix of both.
If Enjin's and Riyo's conversation from earlier is really about them identifying Amo as a trafficking victim, then Enjin's discomfort during this conversation comes from that. And he says it later: he can't deal with women and children with complicated needs. And him having a 3-step failure of a conversation with Amo shows that.
On Amo's part, about being told to cover up after which she snaps and has Enjin shut up, that's also about how Enjin doesn't give Amo the agency to dress however she likes. Even with a groomer in the past who forced her to wear extremely revealing clothes, Amo still has the will and mind to navigate that on her own.
Enjin's role in that position should've only been about giving her the option of wearing something else. It would've still been Amo's decision to do with that whatever she wants but of course, helping Amo to accept what has happened to her would also make her see her current clothing in a different way, making her next decision on what to wear more informed.
