I personally would warn the user to change it and ban them if they don't, but with the more borderline sprays like this one, the decision is up to the staff member online at the time.
So should a player using this spray and similar borderline sprays expect 100% to receive a warning before a ban?
No. In terms of borderline sprays, the decision is at the discretion of the staff member on at the time. I would warn for it, but some staff members might just ban for it.
In my opinion, I find it a problem if one spray can be totally okay and immediately bannable without a warning at the same time. I find it highly inconsistent even when dealing with sprays in such grey area.
It's sort of the reality you'll have to face when playing a game that comes from a staff team, and community as a whole of people from different cultures. When it comes down to it- there's little kids playing here. There's no way to accurately define every position/% of breast/etc. It has to be discretionary. It's pretty simple honestly, if you avoid showing pornographic/borderline pornographic images to kids- you won't have an issue. My spray is a dog who got a haircut like a poodle. It's pretty cute.