I don't understand why implied_sex is invalid, but there are tons of other implied_ tags.
This should probably be changed, I don't see why this would be invalid but I'd like to know if there is a good reason, and if somebody can fix this if there isn't.
I guess there's implied_fucking, which is basically the same thing, but I feel like implied_sex should probably be aliased to implied_fucking or the other way around, this doesn't really make sense.
The wiki page for implied_fucking says it's too ambiguous, but I feel like it would be good to have a tag that could act as both obscured_sex and offscreen_sex so somebody wanting this wouldn't have to use ~obscured_sex AND ~offscreen_sex. I think it would be useful for obscured_sex and offscreen_sex to also implicate implied_fucking, but I'm still not sure right now.
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