Imai Lisa is a third-year student at Haneoka Girls' High Schooland Roselia's bassist. 

Lisa is a friendly and lively girl who appears mature and calm. Despite her appearance, Lisa acts as the mediator in tense situations, and takes care of everyone well. It's because of her that Roselia is able to continue to stick together despite the contrasting members personalities and disagreements at times. She often chides the others if she feels necessary, bringing balance to the group.

Lisa is very caring in nature, and is able to notice when a friend is troubled, usually being the first to try and help. She does her best to do what she can, sometimes to a fault, where she'll put her all into something regardless of her own feelings.

Despite her skills and proficiency as a bassist Lisa believes she is the least skilled member of Roselia, and can get quite sentimental at times as well. She easily cries when her friends, or especially Yukina, reaffirm just how much she is needed in the band or in general.