My interpretation is different. Personally, I believe "maincharacter" is a representation of Sara's despondence and loneliness. She always wanted to be truly loved, and no one really did. She wanted to be someone's main character and never was. So basically, it's a sadder version because her true feelings are coming through.
Whereas "sidecharacter", the original version, is more cheerful, even though it's still delicate and wistful because she's masking her feelings under a veneer of acceptance. You can see this clearly in more recent events.
Tell Me When;
The Place She Falls Asleep At Night;
Nicolas Cage.
Mmm, possibly. Most of the main girls have suffered a lot from what we know. I'll try to assign grades of suffering, to simplify things (an assholish thing to do, but I'm in a hurry and these are fictional characters). This will be mostly a stream-of-consciousness thing because I must hurry
Sensei, a poor bastard. Grade S+(ensei) suffering.
Chika, B+ suffering, mother died, sister sick super sick possibly dead in a few
Yumi, A- suffering, mother is a junkie, father is a criminal pos, dogshit childhood etc
Ayane, C+ to B- suffering, wealthy dad but distant, mother left her
Sana, C+ to B- suffering, dead brother, mother is (was, things are looking up) floundering, probably inherited mental health issues
Makoto, C- to A suffering, decent-ish childhood, but recent events fucked her up real hard, bluejay amongst other things
Miku, unknown at minimum B+, has severe PTSD, something horrid must have happened to her.
Futaba, C+ to B- suffering, body dysmorphic disorder, eating disorders etc. Seems to have had good parents? I don't remember clearly actually
Rin, at minimum B-, self-harm, depression, etc. adoptive parents seem nice though. Biological parents are turbo fucked up (there's a theory here about them I think)
Ami, unknown really, but assuming she is a normal girl and not some demigod eldritch entity, A- at minimum. Dead parents, fucked up uncle, etc.
Maya, more or less the same as Ami, but A+ suffering because she has been looping for possibly millions of years (consciously). How her mind isn't shattered beyond recognition is one of the mysteries at play here (godly origin?). Or maybe her mind did shatter and she's not suffering outwardly because she's already broken beyond belief. There's that trope if I'm not wrong, called "Bored with Insanity".
Molly, C- suffering, good dad, seems to have had a decent childhood in Ireland, far from Kumon-mi. I think her mom died early? Has some issues (LiL-wise she's quite fortunate)
Tsuneyo, honestly no idea really.
Uta, at minimum B+, good family, but she got abused online etc. Caused severe mental health problems and a great deal of counseling.
Io, unknown but at minimum A+, in virtue of being worse off than Yumi. Abused, Raped?
Nodoka, no idea. She's clearly insane though and that must count for something, her mother was sick or something. Tentative A-
Otoha, D-. fairly-normal-upbringing-girl, it's unfortunate she got caught up in this mess.
Touka, E+ to D+, rich af, intelligent and athletic, beautiful and loved (by her mother and sister). father is a dipshit though. The pressure of her position must have caused some level of stress. Will suffer much more in the future because she got caught up in Sensei's mess.
Yasu, is in a similar position to Yumi, Maya and Io. One of the worst childhoods in the main cast. A-level suffering at minimum.
Noriko, C+ suffering. Loving parents and sister. Her great source of misfortune was falling for Sensei. Would have been successful because of her intelligence and work ethic. No health issues physically
Kirin, C+ suffering. Ordinary but seemingly stifling, straight-laced traditional (like Otoha) family. A plethora of mental health problems
Now for side girls:
Sara, A+ and beyond. ultra fucked up childhood, husband left, son died, hallucinations, poverty. In a similar boat to Sensei.
Haruka, unknown but doesn't seem that bad. Fairly ordinary life? She's a predator and deviant, that's on her though.
Kaori, grade unknown but most assuredly shitty. A and beyond.
Chinami, B+. Is ill, mom died, poverty. Has a loving, dedicated sister as a counterweight.
Karin, E. Seems to be one of the luckiest and most normal characters in LiL (if not the most). Possibly caused by her irrelevance. I wish she had more presence, but that would cause more suffering to her, so I'm torn.
Maki, childhood mostly unknown. Now she's suffering a lot now so B+.
Yuki, A. Went through horrid things.
Niki, B. Most of her suffering arose from Akira. Utinam Ne Illum Numquam Conspexissem. Had she never seen Akira, she would have been better off.
Wakana, unknown. High potential for suffering if the painkiller usage is any indication. I speculate B+ up.
Osako, unknown.
Tsubasa, mostly unknown.
Tsukasa, around the same as Touka, maybe a bit less.
Imani, minimum of B+, probably more.
Rika, unknown.
Nao? Well, at this point, I doubt she's even human so...
Conclusion:
It doesn't really matter if you are a main or side character. Are you in LiL? You're going to suffer, friend.
