Cat Companions Maruru and Hachi Vol. 5

All kinds of cats live in the shelter, from newborn kittens to seniors, with various personalities and pasts. Maruru, Hachi, and the other strays who were taken in by Yasuo are now living busy and complicated days there. Then Maruru and Hachi find out the shelter has a secret they weren't aware of! What will happen in volume 5 of this cute, funny, heartwarming and heartbreaking cat manga?