Lucy had noticed certain things about Natsu and weather.
A bright, sunny day, heat bearing down on Magnolia, made Natsu happy, cheerful, and quite often "all fired up". His smiles were the biggest on those days. Summer was Natsu's best season.
The snow usually made him frustrated and annoyed. There'd be times when he would warm up to it, start having snow-day fun, but it definitely wasn't often.
Crackling lightning and rumbling thunderstorms got him excited. Ever since he began to equate Laxus and lighting to a great fight, huge storms had gotten him eager for one.
And then there was rain. Calming, rolling rain. The kind of storm that was just enough to keep people inside, but didn't have them scrambling to prepare for emergencies.
That rain made Natsu dopey, sleepy, and for some reason especially clingy and lovey when it came to her.
Which Lucy could definitely tell right now, trapped underneath Natsu in the middle of a rainstorm, his lips periodically pressing soft kisses against her neck and shoulders.
"I love you," he whispered for the umpteenth time that night.
"I love you too," Lucy of course responded, with a light giggle in her voice.
"I love you," he repeated.
Lucy laughed again. "I love you too. Are you ever going to let me up?"
"No." Natsu snuggled his head against her neck, taking in her scent. "You smell really good right now," he confessed.
"Do I?"
"Yeah… You always smell good when it's raining…" Lucy was silent as Natsu began to play with her hair. "Something about the smell of the storm works well with your scent, I think…" Natsu told her sleepily, a dopey smile on his lips.
Lucy chuckled shyly. "You're always so infatuated with how I smell…"
Natsu sighed and nuzzled against her again, his nose rubbing up against her chin. "Of course I am. Your scent is so nice." Lucy's scent was practically intoxicating to him, especially so during rain. The smell of the ozone complimented her natural scent perfectly… It was even better when his own scent was on top of hers, which by this point, it constantly was.
Lucy gasped as she suddenly felt a low rumble of purr from the man on top of her. She sighed in contentment as she resolved herself to her fate of being trapped under her boyfriend for the rest of the day. It was probably a little late to be taking a nap, but neither Lucy nor Natsu cared as they were slowly lulled to sleep by the gentle pitter-patter on the roof.