Their friends in the guild would likely be very supportive. Happy would probably be over the moon, flying around them and chirping happily. Erza might give them a stern but warm look and offer some words of advice about maintaining a healthy relationship. Gray would probably make some snarky comment at first but deep down be happy for them. And Wendy would be all smiles, seeing two of her favorite people find love with each other.
As they travel, their bond deepens. They start to rely on each other more. Natsu becomes more protective of Lucy, and Lucy begins to understand Natsu's impulsive nature better.
I'm not sure specifically as you haven't given much detail about it. It could be a story about their friendship, a love story between them, or an adventure they had together.