This study investigates how Relationship Marketing strategies contribute to the formation of Brand Love within the digital context of social media, with a focus on the Brazilian digital bank Nubank. Employing a qualitative and descriptive case study approach, data were collected from Nubank’s Facebook, Instagram, and Twitter accounts, examining both quantitative metrics (post frequency, likes, comments, shares) and qualitative aspects (content types, communicative tone, and emotional appeals). The findings reveal that Nubank’s communication strategy combines humour, personalised responses, educational content, and institutional values, fostering affective bonds with its audience. These practices humanise the brand, strengthen customer engagement, and transform users into brand advocates, demonstrating that emotional resonance and authenticity are critical for cultivating Brand Love. The research highlights the importance of relational marketing as a strategic tool for digital-first organisations aiming to achieve sustainable customer loyalty and competitive advantage.