Project A-ko

Project A-ko is an anime OVA series that began in 1986. It was initially planned to be part of the Cream Lemon series of hentai OVAs, but during the production of the series, it was decided to make it into a more mainstream title. The only sequence animated during its Cream Lemon days left in the revised production is B-ko's private bath scene.

Episodes
There are 6 OVAs in the series (though 2-4 and 5-6 were packaged together as Love and Robots & Uncivil Wars aka the Versus):
 * 1) Project A-Ko (1986)
 * 2) Plot of the Daitokuji Financial Group (1987)
 * 3) Cinderella Rhapsody (1988)
 * 4) Final (1989)
 * 5) Grey Side (1990)
 * 6) Blue Side (1990)

Project A-Ko
B-ko as a bath in her mansion starting ~19:40 in the first movie, where to music she reflects on her love for C-ko.

Plot of the Daitokuji Financial Group
B-ko has a fantasy about C-koplaying in her mansion's bath, blowing bubbles and playing with a rubber duck.

Cinderella Rhapsody
An offscene bath/shower by B-ko is implied at 25:45 as she walks onto the scene in the process of wrapping a towel around herself.

Grey Side
After carrying heavy luggage a long distance, B-ko suggests to A-koto freshen up. As she emerges from the steamy bathroom she mentions that she took a shower (offscreen).