Takashina's paper is probably case report. That's why it can be done quite quickly (with no sleep probably 😅).
Comparing Takashina on 1rst eps to this last eps, he looks older. Probably due to th stress of scentific paper conflicts and Tokai's antics. But I like he's the most well developed character in this drama.
While Tokai never change. He must be a vampire? 😂