I also felt quite a bit puzzled after reading this manga. Well, I'm glad that there are mangas dealing with difficult, realistic, true to life or tragedic stories, although being 27, I still enjoy some relaxing rosy shoujo or light josei stories out there... You could say it's almost like Harlequin, you know, when you come home from work and you have to learn for the uni exams, you aren't really in mood to read something super complicated after that...
When I found this, I was going to give it a try, although already the fact that it was marked shoujo and at the same time mature/adult surprised me. Well, I got through that since I read Deep Love... As I was reading, I was shocked at the serious issues, discussed in this manga, if I read this when I was 16, I wouldn't understand a xxxx that was going on (lucky me for being educated but kept innocent all my adolescence). However, I can understand the heroines and their problems, worries, feelings, yes, they were stupid enough to get into their situations but also, I agree that as long as there is the slightest chance and possibility, a girl/woman should try to have their baby because it is true that abortion leaves deep psychological scars that will very probably never heal and also a high risk that the girl can't have a baby in the future (not all are as lucky as the heroine in the 3rd story)... I definitely don't agree that having a baby at such a young age is a good thing but there is always a chance it might work...The chances are rare but I actually admire and support the couple once they decide to try it out and above all, the parents, who are willing to help and stand by their children. For example, in my country during the communist era, it wasn't rare for 18 - 19 years old girls already being married and having babies when finishing high school... Also, Japanese people are educated a bit differently and it might be one of the cultural things that they simply decide to try it out as the boys/men are taking responsibilities, too. There are enough centers for young, single moms in need even here who need support rather than scolding and judgement... Still, of course, it's always better to prevent things than solving the consequences... Therefore, I view this manga as very educational, definitely not the typical shoujo, it's not something I would just give young girls to read but it's a good example of where can irresponsibility lead, to what worries and alienation from the regular life.
Though I wonder, what is happening to the society? Why are there more and more mature, adult, smut stories for the underage kids? I mean, there are so many topics to write about and josei is such an open field for reality and all the previously mentioned things, I don't think that they have place there in the literature for kids... I know I can't judge kids as to how I was back in that age but I'm not old and sometimes the titles "supposed to be" for kids horrify me and half of the titles I read are just about ok to me now (that said I'm a person who's far away from thinking manga is either Pokemon or porn). Nevermind, maybe I'm just meant to be an outsider.