Nidome no Isekai, Shounen Datta Kare wa Toshiue Kishi ni nari Dekiai Shitekuru

Sara is transported to a different world and rescues a boy named Luke, who had collapsed in the forest after being chased. She decides to stay with him as he recovers, but is suddenly sent back home before he fully heals. Three years later, Sara returns to the same world and meets Luke again, now a 25-year-old ice magician and knight who has been granted the title of baronet. Once younger than her, he is now two years her senior and has developed feelings for her. Luke begins to show her affection and promises to repay her with his life.