Toshiue no Hito.

An 18-year-old office worker falls for her boss, who is 14 years older than she is. She works hard to present herself as an adult, but he continues to treat her like a child and turns down her confession. Believing he does not return her feelings, she is surprised when she finds herself in danger and sees anxiety and affection in his expression. His reaction leaves her wondering what he really feels for her.