emkei.czは安全ですか？

The site works and is actually safe. Since it sends the e-mails in the name of anyone you want, it sends it in "offline" mode, without a logged in sender. This will trigger a warning (explaining this) in Gmail and directly move the message to the spam box in Outlook (without any warning). The site isn't evil by itself, but is like a gun: you can use it for a good cause, or you can start killing random people with it.

People are using this site to send you emails that will appear genuine to you and then they will ask you to submit REFUNDABLE Deposits to fake company accounts to offer you benefits of different kinds. Recently in Pakistan, this website has been used to generate fake Emirates Airlines Job emails and the fraudsters looted hundreds of millions of money from the innocent and poor public.