Hello,
Someone has been emailing me affiliate offers everyday for last 3 months.
Even if i mark him as spam or unsubscribe, he will email me from another email id.
This dude uses a new gmail account everytime he sends me an email. In his emails, he is promoting stuff like penis enlargement bible, car insurance, bitcoin investment...etc..etc
I am completely helpless as this dude has my personal email in his database.
And his email is able to bypass spam filter everytime.
This has started to become annoying.
Have you reported it as a phising attack to gmail?
Since it is a different email each time, you'd have to block the gmail domain. Probably not what you want to do.
Depending upon the email client you use, you may be able to set up a rule that sends his emails off to the spam folder depending upon the sender name, subject line or content. Look for something that is common in all his emails and set the rules around that. You may need a few to catch all his emails, but hopefully there is enough in common between them all to stop the majority.
this dude is a professional. He uses everything different in each email.
Infact, i also emailed him back and asked him to fuck off and stop bothering me.
But he still wudn't stop.
I don't know how to do that.
That wud block only 1 email. Not the future emails..isn't it?
Now that you replied, he knows that the email exists, so it is unlikely that he will stop. Always hit the spam button from Gmail, not the unsubscribe links at the bottom, because you end up confirming that your email exists.
You can use Gmail filters to automatically delete by keyword. For example, I assume you don't need "penis enlargment" offers on a daily basis, do you? ?
Here is one I have for all the marketing emails I got on my pro email.

I would go with that option first.
Or, you can try to forge the Gmail "Email does not exist" and reply with that message. Maybe he has a rule that will be triggered by the 550 code. But if he is smart, he will know that the message does not come from mailer-daemon but your own address:

Finally, the only thing that does not change on a daily basis are probably his tracking domains, or the affiliate network tracking domains, which are in the links inside the email. This can not be filtered using the standard Gmail filters, but you can run a Google Apps Scripts, or a Zapier integration, to parse the raw email text and detect the link, then take action to delete the email or not. Probably a bit overkill though 