Nivalis Nights combines storytelling and shop simulation with relationship dynamics, allowing players to interact with characters in ways that shape four attitudes: friendly, combative, romantic, and savvy. The dialogue options do not provide clear indicators, leading to ambiguous interactions that can result in unintended outcomes, such as offending a character or flirting unintentionally. Some characters hint at potential romantic paths, while others are less clear about their intentions. Lead writer Thomas Welsh notes that this design choice intentionally diverges from traditional romance systems in games, which often use clear markers to guide players. The lack of tone markers in dialogue requires players to interpret their interactions, resulting in varied experiences where relationships may develop unexpectedly or remain platonic.