"But secretly...I've always loved you."
-Brittany confessing her feelings to Lloyd.
Lloyd and Brittany first met in 1st grade, when Lloyd moved to Intrepdville with his mom and dad. On Lloyd's first day, the school bully Rodney Glaxer tripped him up and humiliated him in front of the entire class. Lloyd landed on Brittany's finger painting and ruined it. Despite Lloyd trying to apologize and be friendly, Brittany shot him down and took an instant disliking for him.
One day, sometime after Lloyd's humiliating experience in class Brittany was walking her first puppy in Intrepidville park when she found Lloyd carving something on one of the trees. When she asked him what he was doing he ran off crying and embarrassed. Brittany took a look on the tree and saw Lloyd's message "Lloyd luvs Brittany." Brittany was touched by this and wrote her own message on the tree "and Brittany luvs Lloyd too." Of course she could not be with him because at the time she thought all boys were gross then she became cool so she couldn't be seen with him, but she has secretly admired him from afar for many years.
Since then, she has always given off the impression that Lloyd was not worth her time and would insult him whenever possible, either calling him a dweeb or publicly humiliating him. She also showed little respect for him, at least in front of her other popular friends. Of course whenever Lloyd became popular, she would always try her best to make sure it stayed that way, so she could be closer to him. When she thought she had lost Lloyd when he fell through the wormhole, she became very regretful for the way she mistreated him and had a hard time trying to stop crying. But, like everyone else when she found out that both Lloyd and Eddie were safe and had been playing them all, she was most likely angry at him.
She has also shown more hints of affection to Lloyd when his fantasies came to life out of his antenna as she was one of the few kids at Luna Vista to actually like his greatest fantasy alter-ego: The Nebulator. Of course the Nebulator called every girl a "pretty lady" and as such slapped Lloyd out of frustration, calling him a pig.
It would not be until Brittany was accidentally hit by Douglas's love beam device that she began openly falling head over heels in love with Lloyd. She began to act more kinder towards him and sat with him at lunch, as well as defending him from the popular kids. At first Lloyd was ecstatic about Brittany being his girlfriend, until she began to over-obsess about him constantly and so he sought to change her back. Lloyd then changed his mind again when Brittany finally revealed to him what she carved on the tree in the park seven years ago. Realizing that the beam only made Brittany confess her true feelings as opposed to her just loving him under the beams influence, Lloyd then came to the conclusion that despite this, she should still be restored to her former self. Before changing back, Brittany was touched by Lloyd's devotion towards her and promised to never call him a dork again. Of course ironically enough when the beams effect was reversed she instantly resorted to call him 'Nebudork' and stomped away, telling Lloyd that he better watch himself from now on.
However they seem to be on somewhat better terms during the events of Neither Boy nor Girl and although both Brittany and Lloyd bicker with each other over which gender the new kid Zoit should be, they both feel regret after treating Zoit as a pawn in their game and try to make it up to Zoit the next day at school. Of course when Zoit tells them that they will find out which gender Zoit chose when Zoit crushes on one of them, prompting them to argue over who Zoit will get a crush on.
Their relationship seems to improve slightly more when Brittany and every other student in Lloyd's class accompanies Lloyd to Mrs. Bolt's house in order to cheer her up and convince their teacher to come back and teach their class.
"Brittany, like Hello! Are you okay?"
"I'm fine Megan. And Lloyd is oh so fine"
"Lloyd?! Like Nebulon?!"
Megan and Brittany first met in 1st grade, or possibly prior to first grade and have been best friends ever since.