@Ashlinsama I absolutely agree that that's how it
should be read (it's admiration), but I feel like to read it that way you have to ignore the way things are framed and phrased. For example, our MC freaks out at "having a girl in his bed", a phrase which is suggestive towards sex. Now our MC is an isekai'd guy, so we could either see him as 9 yo - meaning they're both children* - or we can see him as his previous age (~35 yo), in which case it's even weirder because then it becomes an adult man thinking about how suggestive it is that a 9 yo girl is in his bed. It's a bit lolicon? An adult and a child in a bed should NOT suggest anything sexual.
* Even if we see both of them as children, it's still kinda weird. A 9 yo would probably freak out more at a crush being in their room at night rather than focus on the bed - the bed is just for sleeping at that age. This is one of the few cases where the MC's behaviour is more in line with an adult man's than a child's...