Are these your own anime creations, or are you copying other characters?
If they aren't your own and you try to make money from it, then you'd likely be sued for copyright infringement. Even if you aren't currently making money, it could still be copyright infringement
If they are your own creations, then there is nothing to stop you from monetizing them, or offering to do commissions. The only thing is that most kids who like anime probably don't have any money.
Perhaps if you diversify into other forms of illustration or graphic design, there would be more scope to find clients willing to pay.
You could sign up for something like Google Adsense and put it on there but I don't know who would pay to see it, you know...
Unless you make graphics for clients.
I just felt like this is what I want to do right now, making graphics for animes that I watch. I'm kinda proficient with using Adobe products and Photoshop especially, with my edits ending up with usually 3k notes or more. A new desktop PC is what I'm aiming for at the moment because my current laptop is too slow for editing. And there doesn't seem to be other payable work with my current skill set that I feel interested in. Thanks!
P.S. I could use ad.fly pages on my tumblr links but I'm asking if there are any other alternatives?