You notice a beetle being born and the beetle is a bikouchu!
Capture the bikouchu to sniff out people.
Walk away and ignore the beetle.
With about a 30% chance of capturing the bikouchu and 70% chance of failing.
If successful, you can get to find one of the following: potion seller, merchant, Shinobazu, Frog hermit, Hinata etc.
When you fail to capture, a bikouchumo will appear and attack you. The hp of it should be about 2 times of your own hp and the attack and defence should be +5 from what your attack and defence is. There are no rewards for killing the bikouchumo.