[Info] Jonghyun's Twitter : The “Balded Head” Display Picture - Original Comic.

Well this comic is has a bit of dirty humour to it
(Viewer discretion is advised):

So it’s a comic about the characters in a war. The 1st soldier got shot by arrows on his arm, the princess help to suck the blood and soothe his arm. The 2nd soldier commoner(?) got shot by an arrow on his lips so the princess kisses his lips.. Well for the 3rd Villian (?)… an unfortunate incident happens instead.

Artist: Unknown
Source: @Ring-broccoli
Credit: soundtracklove@soompi