Yu-Hwa first ends up in the hospital after saving Su-Jin Ji from the accident. Su-Jin is also admitted there but in the V.I.P. room. Yu-Hwa leaves his bed to visit her but faces the monster, which he later learns to be an Another.
After getting discharged, he ends up there again and again due to his frequent encounters with Anothers.
Once Ji-woon Kang tricks Yu-Hwa to get in the hospital while informing Hon agents, so that his wounds can be treated rather than letting Yu-Hwa accompany him at that state.