Responses
I think Ido knows everything because of the forced imprint, he had Accès to every memories of Sejin
I'm pretty sure ido said something along the lines that something happened with the gun twice and thats way its not loaded anymore...so sejin died due to the gun at least twice lol
Its possible, but i think it more like the second one is ido use it to end his own life
Rereading the present, has ido actually gone through many lives after the one where sejin died? The way he knows all the little details in the present, he cant have found out about them from the life in the flashback