まったく最近の探偵ときたら (Series) favorite_border

[DeepL Translation - needs review] Introduction to Volume 1: Solving difficult cases that cause a stir in the world immediately!　His name is the famous detective Keiichiro Nagumo!　It was more than ten years ago when he was ....... Nagumo is now just a bitter old man. ...... He has been left behind by the times and cannot even use a smartphone, when a young high school girl, Mashiro, comes to him and asks to be his assistant.

(Translator: DeepL)