This study explores the impact of monolingual and bilingual robots in Robot-Assisted Language Learning (RALL) for non-native Swedish learners. In a within-group design, 47 participants interacted with a social robot under two conditions: a monolingual robot that communicated exclusively in Swedish and a bilingual robot capable of switching between Swedish and English. Each participant engaged in multiple role-play scenarios designed to match their language proficiency levels, and their experiences were assessed through surveys and behavioral data. The results show that the bilingual robot was generally favored by participants, leading to a more relaxed, enjoyable experience. The perceived learning was improved at the end of the experiment regardless of the condition. These findings suggest that incorporating bilingual support in language-learning robots may enhance user engagement and effectiveness, particularly for lower-proficiency learners.