Responses
I think it was during the time skip.
Spoilers
There was a chapter where he contacted the ML again at the phone booth (it was raining/snowing) and said he missed him but the ML lost his memory so he said “Who was it?” And since then, Mc didnt try to contact him again until the reunion. This is likely when the mc lost his mom and desperately needs ml. It is also implied throughout the chapters at the present time, the mc and his brother did not mention about visiting their mother because she passed away.
Sorry I think I am lost, but did his mother die? When?