Memories of my mother and me ~One mistake~

Chihiro, a mother who lost her husband at an early age, and her son, Tetsuya, have lived a healthy life together. Tetsuya vows to "protect his mother" on behalf of his late father, but his feelings eventually turn into a forbidden love... One day, I decided to go on a trip with Chihiro. She is excited to be able to spend time without bathing with her beloved Chihiro, but is shocked when she is introduced to her boyfriend, Toru, on a trip. Tetsuya can't be honest with Tooru, who acts like a gentleman. One day, I witnessed Chihiro getting entangled with Tooru...