I would not take this connection if that KE flight is the last flight of the day to ICN. If you on DL metal, DL would likely hold the flight for you if you are on the ground waiting for a gate, but I do not know what KE's policy is. Arrivals in SEA are too often delayed nowadays due to gate congestion and ATC congestion. If its the frequent 10 minute delay that is not counted as a delay, you have an extremely tight connection, but hopefully will make it. Probably 1/3 of flights are now delayed by longer than that now though. Just look to AS's most recent abysmal stats for proof of that.