Just finished a belated binge watch of the most recent season of Blue Exorcist, and when talking about it with my friend, we had the idea of "what if Rin saved Yuri that night". We thought it was interesting that Mephisto kept pointing out "the night ends in tragedy" and it was definitely just a "you can't change anything" kind of thing, but we thought it would be amazing if it was Mephisto poking Rin about it, provoking him.
So when Shiro goes in to seal the baby Rin and then has the fight with Satan, but before the Shiemihaza shows up, Rin takes a chance. It's so risky, but Mephisto is ready. Rin in desperation to save his mother, accidentally lights her in his blue flames. Everyone assumes it's Satans last middle finger, and Yuri even thinks she's going to burn, shouting for Shiro to protect Rin and Yukio, before Mephisto makes a distraction, maybe a flash of light, and Rin rushes in and nabs Yuri before disappearing. Mephisto leaves a body double behind, while Shiro is gaping at the boys now in his arms, thinking Yuri is dead.
Rin meanwhile has hauled is weak and flailing mother through a time door, and wondered if he really just did that. Yuri's shouting, trying to get back, and Rin just holds on tight, shouting something like "mom, its gonna be okay!"
And Yuri stops, stares at Rin, has that moment of recognition, before passing out. At which point, Rin panics and takes her to Mephisto, who has nurses ready. He sends Rin off to go finish watching Shiro, or to reunite with his classmates.
The following (what I can only assume will be) fight with Yukio then becomes a "the power of mothers love compels you" where in Rin is like "bro! Lets go see mom!" And Yukio not believing it, until in the third act Yuri, only mostly healed, shows up.
Anyway, just putting this out there now lol