well they are in an enclosed space so it's very possible that he heard when ideum was introduced(or any other time he called out ideum's name lol)? but it's also just as possible that the author skipped the introduction. but my money is on overhearing the name
probably did that offscreen when they were walking to the place
Ideum is far too shy to introduce himself bro TT
Since it’s Jayi’s brother (same name as mentioned previously and other stuff) and Jayi’s brother is probably the one who was Ideum’s first crush sooo
Bro- Ideum never introduced himself to that guy how tf did he know his name