Some spider bites, and definitely tick bites could be a big issue. As someone else mentioned with the circle around the bite. Get it checked out. Save the tick if you pull it out and get it tested. Lyme disease is not something to be taken lightly.
The NSFW isn't to be taken literally. In this case it''s a "I don't want to spontaneously see your weird ass bug and vampire kink bait when I didn't subscribe to anything that would reasonably have it, thanks". The tag gives viewers the ability to opt in.
What? No. Usually I don't answer or downvote criticism because not everyone has to like my/anyone's content and criticism can absolutely be valid. If you're serious though then I'd say sexualizing this image to that degree is quite a leap. I mean, the vampire is Sesame Street's The Count for starters. There's nothing sexually explicit or even implied in either the image or the text.
I would much rather have the NSFW tag be for what it says instead of a general "some people might not want to see this." I don't want to click something thinking it's the latter and get the former. A spoiler tag may be more appropriate if we have those.
Also, this is literally just a meme about bug bites and a vampire bite. The vampire in question being Count von Count from Sesame Street.
If you use tweezers or rubbing alcohol you will make the tick spit the blood back in your sister with all the pathogens with it, this is what causes diseases.
With the right tool the tick is very easily removed with a very low risk of infection.
And properly discard of the tick so it cannot come back. Suggested methods are submersing it in strong alcohol, pulverizing it between hard surfaces or simply lighting the fucker on fire. The guide I've read spoke especially against stepping on them because the ground is uneven and your shoe soft enough to give them a chance to survive. Oh and flushing them down the toilet also gives them a good survival probability.
I prefer the fire approach, fuck those little bastards and diseases they carry. No one survives getting their ass heated to over a thousand degrees Celsius.