Ehhh. Hiromi wouldn't have been my first pick. Actually I thought if it wasn't Satoru it would be Kenya that Kayo would end up with since he was sort of the first one there. You know, the "I didn't step up back then but I am now" kind of story.
That aside, I also want to know how he survived the attempted murder. Lapsing into a coma from the cold I get, so that part of realism was quite nice. But definitely a big plot gap. It was at least interesting that they chose to make a jump in this fashion right at the tail end. Overall, to me, it felt like too little happened in this episode. So much buildup and a sudden slowdown. Which could be intentional to bring out the big guns in a 12th finale episode. But for sure when the ending credits popped up I was going "REALLY? THAT'S ALL?"
Satoru has been doing double the PT and obviously with a purpose, so it's reasonable to believe he is at least capable of some self-defense and he was waiting until he had gotten just strong enough to make this reveal with the intent of trying to take on Yashiro. It's also reasonable to believe that what Kenya was hinted at holding back is actually their collective suspicion of Yashiro and he was waiting for Satoru to confirm it. There was also that phone call with the doc. This could very well be a ploy to get Yashiro to incriminate himself. Now if Satoru is just saving the reveal for himself, yes, I agree that is absolute idiocy to go one on one with Yashiro. Although at that point it's still also on the table for the smarter characters to have laid a trap with Satoru as bait, since we know he is really that stupid.
As for pizza girl, well... when she was 15 he was 29, 11 plus 15 means he's 26 which means right now she's 12. Not gonna make a big appearance here, I guess Kumi could be a relative. Or maybe that'll be the finale, Satoru goes into the working world and stops in on pizza girl already with an edge. I only hope that might happen because Hiromi x Kayo... nahhhhhhhhh...