One day, I received a sales call on my smartphone. Normally, I would hang up because I’m busy, but on that day, the salesperson's voice was pleasant, so I decided to listen for a bit. However, I was so focused on their voice that I didn’t pay much attention to the content. I’m really sorry about that. The salesperson asked me, "Do you know about retinol?" I thought, oh, I need to respond… and I felt a bit flustered. Retinol is an anti-aging ingredient, so it became clear that the...