Thanks for the comment!
Most likely Leo, as he's the most left out and there's little information in the main story and side-stories.
Viewing post in TJ's Side Story + Gallery Is Out Now! comments
Not this, he's more or less connected to the 'The Devil inside you' protagonist hehehe. That's true anyway, gotta get more clear picture with the original timeline 'Bad End Leo' before merging and after merging the timeline with 'Good End Jenna' so it's still welcome information when reading Leo Sidestory