Zach: He was abused mentally, physically and emotionally by his father, Robert. Robert sold an eight-year old Zach to a cult which resulted in Zach in being tattooed with the ink. The end result was Zach becoming mute and might have killed his father.
Dante: When he was young, his hometown of Venice was attacked by the demon Dementius who devoured the souls of innocent people. His father's soul was sealed in a mask by Dementius.
Sally: She was left at an orphanage at the age of one. At a trip to a skyscraper, it was attacked by a villain and she wasn't fast enough to get out. She ended up being gravely and gruesomely injured. If wasn't for Armada saving her when she did, Sally would have died at the age of nine.
Finn: He nearly ended up sacrificing his life to save his sister from being eaten alive by a extra-dimensional beast by letting himself being caught and eaten instead. Worse, this happened because his father accidentally brought the beast for a experiment, meaning Finn almost died due to his father's mistake.
Yoko: Due to her nature of being a kitsune, she has had to watch her family and previous lovers die while she is still alive.
Ryuu: The incident that gave him his powers resulted in him losing his parents. Based off of what he has said, his powers have caused problems for him.
Perry: Her parents are emotionally abusive towards her and left her on a street corner, promising to "come back" for her but, never did leaving her a street urchin before Saint Academy found her.
Will You Hold The Line
The horrible verbal abuse laid onto Perry by her parents such as calling her a danger. Can you really blame the others for going after her parents after they hurt her?
Dante's nightmare near the beginning where Dementius threatens to eat his soul, sending Dante into a breakdown. It is stopped but, Dante is still unsettled afterwards.
I Traveled All This Way For Something
Yoko's breakdown about her deceased loved ones to Zach, saying how she doesn't want to outlive Zach as well.
Integrity, Faith And Crocodile Tears
The whole class's morale going down after the class is made out to be a danger. Even the more upbeat students such Ryuu, Sally, Dante, Yoko and Finn are either angry, sad, confused and/or worried.
Waking Up To Ash And Dust
The bad future in general. Gaea wins and all of Class 1 is either dead, in Fate Worse than Death or alive but, not well mentally. Most of Class 1's children have been orphaned and some have only known a world of fear.
Shane's son Elan is exceedingly lonely, even in comparison to the other children. Instead of living in the Yggdrasil Area, he lives out in a place called The Hollow Fort. He makes plans there to try and defeat / devastate Gaea, implied to be a reaction to the loneliness and his father's death. Elan was born weak in comparison to everyone else and could do little if anything initially. Then he empowered himself using a variety of dark and forbidden arts, going from an infirm boy to a teleporting, lightsaber wielding dark sorcerer. And in the process, was outcasted and castigated for it.
The fates of Class 1 and the staff in the bad future:
Almost all of the school's staff died protectimg the students. The only one who made it out was Bozo, who ended up dying of natural causes a while afterwards.
Zach is captured by Gaea and it tortured via being used as writing ink and is losing sentience. The Iridium Wonders end up seeing part of him being scraped off a board rather painfully. What's worse is he is immortal and the whole reason he became immortal was to stay with Yoko, who ended up being killed by Gaea.
Poor Perry is shot in the head by Gaea, begging for her life. She has become a vengeful ghost who destroys what is ever in her path.
After their deaths at the hands of Gaea, Avajax became a dangerous mountain. In said mountain, he is forever clutching Aster's corpse, who looks like she is resting peacefully.
Mikael and Ellie ended being killed by Gaea when Casper was young, leaving him orphaned at a young age.
Finn died saving his children and other captured metahumans via giving his belt to his son, who's belt was broken in the battle. When Finn died, he exploded into radioactive waste that couldn't even be cleaned up. His death resulted in his daughter disappearing and his dad dying from the heartache of what happened.
Dante ended up being fully absorbed by Dementius who went on a rampage, nearly killing his own daughter in the process.
Sally is one of the few students to survive but, has become a cold Broken Bird in the process due to losing her mother and her squad over the years. She too was nearly killed by Gaea but, survived via transferring to an android body.
Some of Class 1's reactions upon being pulled back while having to say quick tearful goodbyes to their descendants:
Zach and Yoko both end up crying and holding each other, vowing to stop Gaea for their children's sake.
The normally stoic Aster ends up crying over not being able to protect her squad in the future.
Sally is rather shaken up by hearing the truth of the future and the pressure to stop Gaea, resulting her running away from her squad to go home.
Ash seperates herself from the others and breaks down in tears.
Finn is frustrated which results in him punching the wall and yelling upon coming back. He ends up locking himself in his room, ignoring his sister's phone call and going to sleep.
Perry is emotionally confused and runs desperately to find Orthus.
Ryuu reads the letter his adopted son in the bad future, Genbu, gave him which sends into tears and leaves the library to find some sort of relief.
Dante learns that during the spider battle, Dementius stole Raffaello's soul and left a taunting message. The reveal of this prompts Dante to yell a Big "NO!".