Why 8018?
In order to love the pairing, I think you need to be familiar with two facts that have been presented to us about these characters. With Yamamoto, he is cheerful and always finds the humor in even the most grave situations. In Hibari's corner, we know that he is freakishly independant and has a thirst for confrontation. It's the extreme polar opposite behavior that seems to make these two more appealing together.
Personally, I won't lie, I love the abuse. It's realistic. If these two actually did get together and it wasn't just a fandom wish, I haven't the slightest doubt in the world that Hibari would constantly beat on Yamamoto or simply ignore him and that Yamamoto would either be very accepting of this fact or he would constantly poke at Hibari, just in the right spots to get a reaction.
In the fandom for 8018, Yamamoto usually (like 99.9% of the time) takes on the role of the younger seme while Hibari upholds the role of the older uke. This I believe is actually pretty accurate. Back to my previous statement, Hibari wouldn't be very caring thus obviously not very affectionate in a relationship, even a romantic one. The likelihood of him taking the initiative to actually show this would be slim to none unless he got something out of the deal (and oodles of love wouldn't cut it). Putting him in the uke position fits perfectly for him because this means that he doesn't have to change himself to better suit somebody else which would definately sit well with Hibari.
Now we toss Yamamoto into the mixture. The fun part about him is that he isn't very complicated when it comes to his train of thought. He doesn't butter things up even if at times he's awkward or trying his best. Basically: he tells it like it is. This would mold well with Hibari who quite obviously wouldn't take too kindly to something being buttered up and decorated with flowers and heavenly scents. The biggest thing about Yamamoto, however, is that he's playful and isn't afraid to be so. It's his best quality, the amazing ability to have fun. Hibari doesn't have fun or at least not the things we might find fun. So this trait would be like a whole new experience for Hibari.
Now here is where the abuse comes into play. Obviously Yamamoto is playful and he is likely to keep that playful nature in a romantic relationship as well. Being playful to Hibari probably wouldn't wind up in good results despite the many pleas and counters the Reborn fandom mutters. This is the realistic fact I adore so much between these two. The simple fact that in this relationship, fans don't sugar coat it to make it lovely. It's lovely with its cold, hard truth.
Alright so I've ranted about them for a while about putting them in a fandom-based relationship but lets not forget the simple stuff too. Romance and fangirl wishes aside, these two distant relationship is actually something I admire as well. They don't get much interaction together but you can see in the little things they say and do that there is at least a hint of admiration between them. No, not romantic but a simple admiration for strengh and ability. For example, during the Varia matches, Hibari takes it upon himself to actually go out and watch Yamamoto's battle. He was so busy training with Dino all the time but he managed to take in our favorite Rain Guardian's one-on-one. This I believe shows Hibari's interest in Yamamoto's abilities. It's not extroverted praise but it's still praise in a Hibari sort of fashion.
I hoped that helped shed some light on why I adore this coupling so much and maybe it helped you see that this isn't too much of a crack duo after all. Not all crack duos are fandom created: remember that and always keep an eye out for the small details. You may be surprised to find that that is what draws you in whether it be a character, a relationship or even a series.
Praise be for 8018 ♥
