I just did a hangout with him so the photo will say 2/2 but the "New Hangout Available" didn't show even before that. Just wanted to say this now.
I have Semeru at 10 hearts but 10A (and by default 10B) aren't triggering to show I have a new event. I finished 9B recently in game (technically one in game day before I hung out with him today). I have searched this myself, but it has been unreliable because people on Reddit keep saying you need to wait for him to be on land to hangout or do hangout events PERIOD and that has NOT been the case as 9a and 9b were me asking him to hangout while he was in the merfolk kingdom.
His wiki says NOTHING about requirements for 10a and 10b so I am really lost.
Do I need to wait for him to come on land for this event? Do I need to wait for different weather for it to even trigger that there is a new hangout available? Since I am not getting the banner across his icon, I am unsure of ANY requirements needed...