In 2015, he starred in the film Shoot Me in the Heart, based on the bestselling novel of the same name by Jeong Yu-jeong. He had his first leading role on television with teen vampire series, Orange Marmalade, based on the webtoon of the same name. In the same year, he appeared in the Korean War film, The Long Way Home. Veteran actor Sol Kyung-gu, his co-star in the film, strongly recommended Yeo for the role of Yeong-gwang, and only signed the movie contract once Yeo's casting had been finalized.