There has been a sharp increase in traffic to my site from third-party sites, why?

Question

Search Engine Optimization

I have a website dedicated to children's quests.
podarikvest.**
The visitor comes mainly from Yandex and social networks. But yesterday, at about six in the evening, visitors from many third-party sites (mainly from children's online stores) abruptly went. And it still continues. I cannot understand why this happened. On all these sites, I can not find links to my site. We did not undertake any advertising campaigns or other marketing activities. The maximum that we do is invite people to our VKontakte group. The rest of the traffic to the site is all organic from Yandex. I can’t understand where the flow of these users suddenly came from.
I checked the site through several SEO services and there are not many external links to the site, and I know all of them. Those. none of these dozens of children's online stores found external links to our site.
Maybe someone came across a similar situation, what happened, why so many users went to the site from some obscure (albeit thematic) online stores? On the one hand, it seems like you need to rejoice, on the other, all this is somehow suspicious and scary.

Answer 1

See if there are any referrals from sites whose domain names are similar to this one: traveltop100plus.ru
If yes, write to have them removed.

Answer 2

Some mud @ k apparently mixed up the letter in the link. I would be happy in your place

Answer 3

add to GWT, it will show who links