Okay. So you know that Usagi was lazy, clumsy, tardy, and a crybaby. What else is there, you ask? Plenty! She might have been all those things, but one thing that had always set her apart from the others was her ability to befriend just about anyone. In the anime, it was she who approached Ami, Rei, and Makoto despite their bad reputations. Usagi didn't care about status; she wasn't like other people who only looked on the surface. Yes, it was true that she teased others (Umino, Rei, and Chibiusa, for example), but it was never done with malice. That was why, in the R movie, the four Inner Senshi pleaded Fiore not to hurt Sailor Moon. It wasn't just because they were sworn to protect the Moon Princess, but also because if it weren't for her, they would have never met each other.

In the S season, when there was animosity between the Inner Senshi and Uranus and Neptune, Usagi did her best to keep the two groups working together. Their missions might have been different, but Usagi believed that if they worked together, they could overcome obstacles. (She was right, of course, as evident in later seasons.) And when Uranus and Neptune wanted to kill Hotaru for she was both Mistress 9 and Saturn, Moon protected her. Hotaru was a fellow senshi, after all, and an innocent child. She was merely possessed when she swallowed Chibiusa's crystal which led to the pink-haired girl's coma. (Imagine trying to protect someone who has practically killed your daughter. That's tough!)

In the first part of Stars and the continuation of the SuperS/Neherenia saga, Usagi still kept the senshi working together. Even though she left hastily to rescue Mamoru in Neherenia's stronghold alone, she still managed to unify the two groups (Mercury/Uranus, Mars/Neptune, Venus/Pluto). It was because of her that the Inner and Outer Senshi learned each other's strengths and to rely on each other. And it was because of her compassion that Neherenia received the energy she needed to start anew. (Neherenia might have been the enemy, but she was only misunderstood and misinformed and lonely.)

In the second part, Usagi became the peacekeeper again... this time, between the Outer Senshi and the Starlights. Since the Outer Senshi (especially Uranus) considered the Starlights a threat to the safety of their princess, they wanted Usagi to stay away from them. But she was stubborn. She realized that since they wanted to do the same thing -- to defeat Galaxia -- it would be better if they considered each other as allies.

Usagi cared deeply about her friends. And I'm not just talking about the other senshi. (Yes, she did have friends besides them.) Although she didn't spend as much time with Naru, her best friend, after becoming Sailor Moon, she didn't cut off her ties with the girl completely. In the first season, when Sailor Moon discovered that Naru had fallen in love with the wrong man, Nephrite, she tried to warn the girl of the dangers. It had been hard for Usagi to do it even when it was for the best. And then when Naru and Umino became a couple, Usagi supported their relationship.

And what about the bond between Usagi and her feline guardian, Luna? In the beginning, Luna doubted Usagi's abilities as a Senshi, but as time progressed, she saw the changes in her young charge. Oh, Usagi was still whiny, clumsy, and all that, but she had learned to accept her responsibilities. Anyway, the love between Usagi and Luna was very obvious in the S movie. You see, Luna fell in love with Kakeru, a sickly dreamer. Of course, that created a problem because Luna was a cat and Kakeru, a human, already loved someone else. As Super Sailor Moon banished the evil snow queen whom Kakeru named Kaguya, she wished that Luna could be a human even for just one night. The Ginzuishou granted her wish and Luna was able to tell the man she loved to get well. Afterwards, Luna realized all along that Artemis was the one for her.

So yeah, Usagi and Luna were very close-knit. And if you think about it, their relationship was a bit complicated. Luna wasn't just a guardian of the Moon Princess, a mentor for Sailor Moon, and a friend of Usagi's. Luna was sort of a mother-figure too.