Now that you asked that, I am no longer sure hahaha from what my mind believes, he did stay a long time at the rift, but I don't know if it was 6 years.
If time doesn't flow the same with the two, maybe indeed J time skipped~
About sa-young making the pact, maybe because at first he wasn't sure if he was J, and just wanted to get him close to confirm it? Idk, my memory is all jumbled up.
Please do tell if you find the answer in the novel!
He's in the rift for 8 years - time flows a bit differently, but you do eventually find out why he can't remember it. It does get crazy... and sad. I read the novel but am taking a break because it was sad.
About the pact - Sa-young didn't know it was J. He just liked him and wanted to get closer to him. I'm not sure if it was in here or just the novel, but Sa-young makes a comment about not knowing he was J before. I think he was interested, and knew Eu-jae had strong powers, but he didn't start to suspect he was J until much later...
j was in that rift for 8 years, he spent a lot of time fighting alongside his teammates with the monsters. i think after a few days or a couple of weeks everyone ended up dying and my guess is that time had a different flow in that rift, so when finally killed the master / big boss of the rift he finally fell out of that rift and into the real world but it had already been 8 years.
and sayoung did send him on a couple of missions, the first one was the one where he purposefully got caught by the men and knocked them all out which after a while resulted in woojin (I'm not sure about his name but that long haired guy) giving him two tickets to the auction.
ah okay! thanks guys. i think the part that gave me the most questions was the one with the basilisk sword and the fact that it recognized golden hair guy as the creator, even though when j got it in his original timeline, golden hair hasn't awakened yet (so he couldn't have made it). the only possible explanation in my mind was that j emerged in a new timeline, 8 years later, in an alt world.
i'm a little confused... maybe someone could clear this up for me? how long did J actually spend in the rift? he talks about sleeping and waking up there, but he wasn't there for all 6 years right? also, sometimes he refers to his timeline as "in my world.." which makes me feel like he entered an alternate timeline, but isn't it just a time skip? the fragment business just makes this more confusing for me.
finally, what was the point of making that pact between sa-young and eun-jae, if sa-young didn't know who J was and ended up not using eun-jae for any missions?? is it just plot?
anyway i love this manhwa idk if it's the mix of translations or the pacing, but i'll get around to reading the novel eventually lol