6E 1385 then KE 660 at Bangkok
Chennai → Bangkok → Seoul
Timetable, Bangkok time
10:306E 1385 from Chennai at the gate
09:50KE 660 to Seoul leaves the gate
23 h 20 apart on the timetable, overnight
KE 660 leaves 23 h 20 after 6E 1385 arrives on the timetable: more than half a day, so not a connection we count.