Posted on his/her Pixiv, the character remains a mystery to me. If anyone have a hunch what(who) the character is, feel free to contribute.

I myself think she is a minor character from Moomins (Moomin), seen in the '90s animated series in a few episodes as an extra (background character). No confirmation about this though.

Target of identification: post #313777

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Don't want to; not like I will use that site everyday.

Ok, google translates the tags into this:

R-18
Please do not pull on the guy
Why is it when it comes to this

• Kemono

Pokemon
Mesukemo
Advanced
Climax from the beginning
Cover fraud

(I'm not joking)

Dunno if this helps you (probably not).

The tags apply to various images in the gallery, of which that's just the cover image. The gallery name translates to "graffiti summary 3", which could be thought of as a collection of sketches.

As for that image, the big text in the upper right reads "Mature housewife dog" "Ruriko's 36th birthday". That tells you the character name, but I didn't have much success Googling for it.

I can't make good sense of the text on the left... something like "Le*a's advertisement about cumming inside a familiar housewife". *shrug* Maybe it's supposed to read "A Le*a publication about intimate housewife vaginal sex."

These are the reasons that make me want to learn Japanese. I know a few (<5) kanji, tho, but I can't make sense of anything :/

You'll want to learn hiragana, katakana, and basic grammar and verb conjugation rules. Lots of edutainment tools for that, and lots of community colleges offer at least one course on Japanese that would easily cover all of that and then some. Beyond that, I use a kanji lookup tool. I'm not exactly fluent, or event literate, either.

I have high confidence in my translation of the upper-right text, but relatively little confidence in my translation of the lower-left text.