SHOUTOUT TO MY FELLOW #teamSensei!!! THIS IS PROBABLY THE FIRST MANGA THAT BROKE MY HEART!!!! I WON'T RATE THIS BC I LOOOOVE THE STORY AND THE ART BUT I HATE THE ENDING SO MUCH I JUST CAN'T!!! Sure, Mamura is a great guy, but Sensei is too!!!
tho sensei is partly at fault here. He could've just asked Suzu to wait until she gets to be an adult or something
yea yea Mamura is a great guy, but SENSEI!!!!!!

Suzume is hurt because it's obviously her first love and she's confused, moreover she understands that they cannot possibly be in a relationship. And Shishio-sensei,well, he fell in love with a child even worse - with his student and he feels pretty bad about it. I think one of the best moments in manga when he looks at her and thinks: we are from different universe. It really speaks well for him: he gets that it's a crush but also understands that it will not lead anywhere. And I must admit he behaves decently, well, yeah, I don't like how he grabbed her sometimes to hug (just a couple of times) or to take someplace to talk but other than that (THANKS GOD) he doesn't do anything improper, they just hold hands couple of times that's all and I cannot express how much I'm happy about it.[
I personally don't advice you to read pass their breakup (oops, SPOILER, but let's be honest it was the only way to handle it) because it ended just perfect and the rest of manga, well... ¯\_(ツ)_/¯ I read it till the very end but honestly the rest of the story is just not good and plain and boring and there is no decent explanation of this deep love Suzume and Mamura sharing in the end - their relationships had no development whatsoever.
Moreover, I liked Mamura at the beginning, I knew it would be a love triange here so I thought: it's a good idea for them to be together, 'cause they are same age, interests, degree of maturity and all, what can go wrong? Well...
EVERYTHING. ≧△≦ Mamura is a d*%"head, really, he's a little abuser and even it implies that he supports Suzume all the time while she's in pain but... no, not really (he hugged her after she got rejected once and he did pretty much nothing after she got her heart broken. Oh, yeah he gave her his scarf pffft) Moreover, he's very rude towards her all the time, even when they become friends he still acts very uncaring and call weak and stupind, even when he confessed to her he called her an idiot＞＜, he hits her forehead (not hard but still it's an abuse) and do it reguraly with no reason, screams at her and ignores her opinion etc. This is nowhere near the romantic love story I expected, even the last page was awful (SPOILER ALERT: when Mamura is going to propose her he thinks smth like "I have to make a lame speach and I will never accept "no" for an answer from you, idiot" - he neglects her real feelings and obviosly he's not very fond of being romantic with her).
Secondly, their love (Mamura and Suzume) stars really strange, first they pretend to be couple, then he confesses (again), then they are a couple for real blah blah and there is a strange twist when at one moment Suzume is talking to her friend about how she felt - that she's confused and she doesn't know if her appreciation of Mamura is as a friendship or romantic feeling and in just in a moment she's rushing towards Mamura's house to ask him out (WTF?!). And again, I can relate to it: she likes his company (althought he's a d*&%) and want to spend more time with him but where all those feels and emotions that we see in the end of manga are came from? Where? They had a couple of dates, he screamed at her in front of the aquarium, then dropped a toy on Suzume's head (soo, soo romantic (not really), they went to a trip on vacation... sooo? Once again why are they so in love? When did she start feeling it? When did she finally recovered from the pain her previous love gave her? (Well, there is this moment in a manga actually but it's not very conviencing) It's like there is A LOT missing in the plot and the ending is just duuuuh - why did mangaka need to make this strange side story about Shishio 6 years later (SPOILER! he meets a girl living next to him and they talk a couple of times and it ends just in the middle of the conversation! If you really wanted to make it clear that he started something new (yeah, just six years later and he has "sad eyes" from that very love story with Suzume. *rolls eyes* it looks even more stupid comparing with how little time Suzume needed to start a new love, oh, i'm sorry A NEW EVERLASTING ROMANTIC TRUE LOVE (=_=) [/spoiler]
Well, anyway... As you see the plot is not bad (it's not good either, it's just usual shoujo manga, you know) and the storylines and love triangles are just fine, and I even think the student-teacher love story wasn't that bad (I still don't approve but at least it was realistic: confusing, uneasy and inappropriate and ended accordingly, and yeah, you still can sympathize with both Suzume and Shishio even if you think that those kind of relationships shouldn't exist). But the second part of the manga is just not worth of your time.

BTW, there are a lot of really forced twists and coincidences (in fact, the whole Suzume-Shishio storyline is a conjuncture): Suzume meets either her teacher or Mamura in huuuuuuuuuuuuuuge Tokyo all the time no matter where she goes: to New Year's Festival or to a temple etc, needless to say they bump into each other in school all the time, it looks fine at first but in the end it becomes really annoying and unnatural and sabotages the whole story.