Rou Zao: MusSoap

Soapy is a block of soap that loves muscular guys, especially his Master. Until one day when a rival, the liquid-soap Creamy, appeared in the bathroom! From jealous love-rivals to becoming soap bros, random appearances by the Master's family, and Soapy-kun's mysterious past, a hilarious story will unfold!

(Source: Books.tw, translated)