This is Senko from sewayaki kitsune no senko-san. Do you think her swimsuit panties are the same colour as her bra (brown), or like her skirt (red)? I believe she is wearing a flounce top swimsuit and skirted bottom. I don't know if girls at the beach wear different colours for top and bottom, or if the skirted bottom and swimsuit panties are a single piece of clothing and thus completely red.

Thanks in advance!