Well, so I actually came across another answer while around Youtube. It's explained in this video (no blisters or any kind of disgusting things are shown, so feel free to check it out)
The main treatment for a blister usually revolves around pricking it with a needle to drain it (which could cause an infection), or let it be (which is not much of a treatment). But in this case, the girl in the video talks about Benzoyl peroxide, a substance used in acne treatment that can dry out the liquid from the skin
Basically, she takes an acne cream containing 5% Benzoyl and applies a small amount of it on top of the blister. Later, she covers it with a bandit and according to her it was completely flat the next day.
I (fortunately) didn't try it myself, as I didn't get any more blisters, but I thought it was worth mentioning as it doesn't involve anything invasive.