The ottcoth account has just finished sending 200 emails.
There could be a spammer, the account could be compromised, or just sending more emails than usual.
After some processing of the /etc/virtual/usage/ottcoth.bytes file, it was found that the highest sender was sontaya.s@ott.co.th, at 24 emails.
The most common path that the messages were sent from is /root, at 73 emails (36%).
The path value may only be of use if it's pointing to that of a User's home directory.
If the path is a system path, it likely means the email was sent through smtp rather than using a script.