Ketchup Mayonnaise

Atsushi's bar-tending mom remarries to a rich, strait-laced (if not slightly old) salaryman. They move into their new house, and he can now sleep in a bed fit for a Prince! With the union, they've become one big happy family with him, his mom, his new step-dad, his step-dad's kids Peter and Kurara, and the ghost of his ex-wife....wait, what?!