Well not really... some country can't have bee's (like africa) so mosquitos replace them
You know what Thanos say : "a soul for a soul" (sorry bad english I know it's cliche but just so you know if I made any mistake)
@Lynkaster and that's were you are wrong kid! Science proved that they are indeed usefull for the earth ecosystem because they do exactly the same as the bee for the flower (I don't't know the english word) and it's only the female who sting!
Even if we all know that he will come back and probably tell his feeling to her : I really fucking hope it won't be the end and the mangaka will still keep doing this serie!