He has a kind nature, a sense of justice, and is willing to risk his life to catch vampires. However he is unpredictable and hard to read at times, such as the instances where he saved Hayan from being revealed as a vampire. He does possess quirky mannerisms, such as his infamous morning routine, jealousy towards other men Hayan encounters, and underlying pettiness. The captain is confident in his ability to fight, very perceptive of his surroundings, and has a strong sense of duty. He tends to be very chatty in even the most serious situations and can let his cockiness get the best of him. Whenever Hayan asks how he was able to complete a difficult task, Euntae would boast that his skills are first rate, but does not go into much detail. When confronting his sister, he lets his guard down and appears remorseful. He is overprotective of his loved ones, showcased by the lengths he went to save Haeun from being turned and his nonstop care for Hayan when she was unconscious.