Welcome to Gaia! ::

Huge explanation on finding fanart ahead! :O

Your best bet is to get the Japanese version of both of their names from Wikipedia or a similar site, stick them into the search at google.co.jp (all the buttons are in the same places - I can't read Japanese, myself) and then check around in the results, and the image results, that come up.
It's a good idea to try and memorise what both their names look like in Japanese for the duration of the search, so you can ignore everything else. (Unless you know Japanese, but I'm working on the assumption you don't.)
If you see an x between their names somewhere, there's a good chance you're on the right track!
If you manage to find a fanart site, don't just look through it and then get rid of it, check the "Link" section, since most fanartists have favourites or affiliates there, many of whom probably like the same series. (If not pairings.) If the sections are marked in Japanese, hover your mouse over the one you want to know and read the text of it from the bottom left frame of your browser.
イラスト (irasuto) is the katakana equivalent of the English word illustration, and commonly refers to fanart.
BL is BL, GL is GL and anything marked "NL" is het.
Age ratings are generally clearly defined, but be cautious nonetheless, if you think there might be something unsuitable for you. (I don't want my advice indirectly causing you scarring, after all!)

You can also look up a guide to joining and using pixiv. This is akin to the Japanese version of Deviantart, or other similar sites. Do the same thing with the names for searching there as you would in google, if you've made an account. (People who haven't aren't able to browse the website at all, basically.)

You'll need to have the East Asian languages installed or working on your computer for any of that to work, though. You can easily google a guide to making your computer display these. (Most of the fonts on your computer that display as just rectangles or squares are actually for Chinese, Japanese, etc., but your computer will not normally display them.)

Phew! Hope that helps! It takes a lot of trawling through websites where you can barely understand anything (for me, at least) and time, but if you're determined, you could potentially find some good fanart.
I only really do it when I'm a) desperate and b) have reams of time.

Be mindful, though, that many fanartists aren't exactly keen on people randomly copying down their pictures - make sure to say that you didn't draw them if you do repost something, and it's best to just keep any pictures from websites that have the "Online Fanarts Protection" whotsit on them just for your own collection.

And don't abuse this advice, alright? 3nodding