For the Leo if he was like Touya Todoroki post headcannons :
Leo is usually insecure of himself because he always has to go to the medical department after missions because he will get serious burn wounds after and he also feels very guilty about the worry looks of others when they saw them.
Leo usually like to train with himself because his brother usually force him to take a break every time his burn wounds would appear.
Randall usually would help cool down Leo's wounds after mission.
All of his family members even the tsudere ones would worry for Leo since every mission he would go home with new sets of bandages.
When he is upset sometimes his flames got out of control and will set himself on fire, there's a time it's so serious that he almost got himself killed
Fuegoleon will always make Leo partner with someone at mission because Leo usually would ignore his injuries and he will also sent Leo to the infirmary before calling Leo for a report
When Leo was younger, he has poor control like Noelle but unlike Noelle he would get injured every time making it difficult for him to control properly
Mereoleona doesn't show but she would worry for Leo sometimes she would send Leo straight to recovery mage every time she sense something is wrong with him
When he first unlocked his magic, he showed his brother first and suddenly pain shot through him where set his fire and it was smoking. He still remembers Fuegoleon's face when he look at Leo with worry and confusion
Leo would usually train outside his family estate at a forest not to far from it
The forest was burned down when he accidentally loses control as the accident that almost took his life
Leo was saved by Fuegoleon at the night of the accident and he was on coma for 3 months after it happen
After Leo awoken, he was lectured by Fuegoleon about how irresponsible he was to not told him about and it became one of their biggest argument they have
They worked it out after apologizing to each other since it lasted for days with the other attacking the other when he snapped at him about the kingdom rumors and disappointment he was as he rants and wails about his problems
Ever since the incident Fuego became closer to him and always defend Leo when Leo was bought up because of something bad usually for not being able to handle his magic
Since Leo can't control his magic that much he became closer to Noelle
Mereo usually would bring Leo to some of her training that requires mana control to help him
Leo usually trains without his clothes on because they would get burned because his magic is so destructive it would burn everything it touches
Leo usually would cry because of the pain his magic would cause him
Leo's hair actually has a few strands because of the stress of having to exceed expectations he got from the Nobles and Royals alike
Leo as a child usually has to go the medical department since he has very serious burns
Fuegoleon usually would try his best visit his brother while he heals and do paperwork when he's asleep
Leo and Noelle would usually play kick ball, Leo is pretty good at it while Noelle is pretty basic about it
For the Yuno and Leo as the Yuta-Rika duo :
Leo died in front of Yuno, Yuno face doesn't show it but inside he was in denial and begging Leo not to die
When Leo transformed, Yuno was lost in his thoughts that he didn't realize the enemy was going to strike him and was snapped out of it when Leo defended him. He didn't realize it was Leo until Leo spoke with his voice being disoriented "Yu....no.." after that he just looked at him with horrified expression
When Fuegoleon and Mereoleona saw Leo's body, Fuegoleon was actually crying with Mereoleona just staring at his body as she can't process what actually transpired
When Yuno explain to them that Leo is a curse spirit, Mereo demands to explain how and why it happened with Fuego clutching his brother's corpse
When Leo appear in his cursed form, Fuegoleon cried and touched Leo's head while repeating saying to him that he was sorry he failed to protect him. Mereo on the other hand stormed out to blow off some steam after she asked him why he is actually back trying to hold her emotions (Leo didn't answer her even though he knew why)
After the battle and funeral, Fuegoleon cried with an awkward Nozel not knowing what to do as he rants everything about Leo and his 'supposedly' failure to protect them
Leo would appear when Yuno is in danger, One time When Yuno was about to get stab Leo suddenly appear behind him and almost crushed the person if not for Yuno stopping him
Since Leo was attached to Yuno, He would follow him around and Leo has actually tons of tea from the golden dawn because of it
Leo doesn't usually speak but when he does he only call people names or only saying one sentence as so
There is a time when Mimosa was about to get attacked with a spell, Leo appear and protected her while screaming "Protect"
When Yuno and Fuegoleon team up, Fuegoleon keep glancing to Yuno with a sad expression but he can't help knowing Leo is around him curse
Mereo doesn't admit but she was kinda glad when Leo was still somewhat alive even as a curse
Leo can still use magic even as a curse and it even became stronger since then
Asta when he meets Yuno would also greets Leo even he couldn't see him
When they got the explanation How and Why Leo turned into a curse, They are actually relieved that Leo wasn't curse because of something evil
When Leo was released, Fuegoleon goes into his grave for the night and attempt to speak to Leo and Mereo would look at the sky and promising Leo to take care of his idiot brother and his friends
When Yuno uses Leo's magic, Fuegoleon would be reminded of Leo and when Yuno uses it for the first time he almost cried
Ever since Yuno was given Leo's magic, Mereo would grab Yuno from golden dawn HQ to train with her because she wouldn't want her brother's supposedly successor to be weak and would helped Yuno train using Leo's magic
Leo's (Rika's) curse form :
Leo as Touya when he was training alone at the forest :
*The day of Leo's incident where he was almost killed*
Leo when he showed his magic to Fuegoleon :
Leo's hair turning white because of stress (imagine red as Orange and Blue eyes with Green eyes)
Leo in the hospital as a child
