Gmail is selling me Russian brides

I typically use uBlock origin and don’t see the ads in gmail. Recently trying to get an extension to work on gmail I turned off uBlock origin. When navigating over to my Social tab I saw an ad for a NSFW service (see image below, first ad).

Snapshot of my Gmail “Social” tab. The first ad — targeted incorrectly to my wants, but perfectly uses my age group

I am 35, so clearly Google is using info it has on me. But I am married with young kids — google photos is full of pictures of them — so I’m curious from where google deduced that I’m likely to click on this link.

A snapshot of my gmail Promotions tab

The Promotions tab didn’t have unseemly ads:

The ad on the social tab concerned me. Google uses smart targeted ads to figure out what I want — so my family/friends who see my gmail ads would deduce that I’m chatting with mail-order brides on gmail.

There is a more info button that links to your google profile with options as to whether google can use youtube / search / etc. to target ads. My profile (below) lists topics I’m interested in deduced from “Activity on Google sites.”

List of topics Google deduced I’m interested in from search / usage history. Russian mail-order brides is not on the list.

So some questions to you:

Any interesting / funny / educational story you can share with us of your own google-ad experiences?

Where does google deduce your interests from?

How to blacklist certain ads e.g. NSFW