
So, MC obviously went to his trip and we have a one or two years time skip, I don't remember, but MC eventually comes back and he find that the ML is now a guild leader, but most of all, have a bad reputation of being rude, killing everyone and anyone etc..
ML is mad at the MC but he eventually forgives him when MC finally gives him his number and they started chatting through calls
ML has a dog, MC has a cat and when MC was taking his cat, Mocha, to the vet, he met the ML (ML recognized his voice, MC didn't, worse, he hated him because he blocked the entrance when he was in a hurry. The poor boy was just too shocked and didn't know how to introduce himself to the MC)
ML ended up going to MC's university and finally, introduces himself to him. It should happen before chapter 20 in the manhwa but they send A LOT of time developing the game aspect of the story (〜 ̄△ ̄)〜
You can read the English version here : https://www.novelupdates.com/series/the-symbiotic-relationship-between-a-newbie-and-an-oldbie/
Thank god they are sealing the ML away. Now, give me the MC's back story. I want to know what does he have on his chest, did someone lock him somewhere or something, etc...