Games like Nanomon Virtual Pet
Games like Nanomon Virtual Pet include Tiny Pasture, Fish to Dish: Idle Sushi, Cast n Chill, Cornerpond, and Spirit City: Lofi Sessions. We matched them by the tags players give Nanomon Virtual Pet on Steam (Desktop Companion, Creature Collector, Idler, Casual, and Relaxing): closest matches first, and among equally close ones the better-known games.

Tiny Pasture
Shared: Idler · Creature Collector · Cute

Fish to Dish: Idle Sushi
Shared: Desktop Companion · Idler · Creature Collector

Cast n Chill
Shared: Idler · Relaxing · Creature Collector

Cornerpond
Shared: Desktop Companion · Idler · Creature Collector

Spirit City: Lofi Sessions
Shared: Desktop Companion · Creature Collector · Relaxing

Slime Rancher 2
Shared: Relaxing · Cute · Creature Collector

Maltese's Fluffy Onsen
Shared: Desktop Companion · Casual · Idler

DAVE THE DIVER
Shared: Casual · Relaxing · Pixel Graphics

Cookie Clicker
Shared: Idler · Casual · Collectathon

Desk Paws
Shared: Creature Collector · Idler · Casual

Chillquarium
Shared: Creature Collector · Idler · Collectathon

Rusty's Retirement
Shared: Idler · Desktop Companion · Relaxing

My Little Life
Shared: Desktop Companion · Idler · Creature Collector

Shelldiver
Shared: Casual · Idler · Relaxing

Stardew Valley
Shared: Relaxing · Pixel Graphics · RPG

Birdwatching Notebook
Shared: Creature Collector · Idler · Desktop Companion

My Little Spider
Shared: Desktop Companion · Creature Collector · Collectathon

Digseum
Shared: Idler · Casual · Relaxing

WEBFISHING
Shared: Casual · Creature Collector · Cute

Unpacking
Shared: Relaxing · Casual · Cute

Tiny Aquarium: Social Fishkeeping
Shared: Creature Collector · Idler · Collectathon

Placid Plastic Duck Simulator
Shared: Relaxing · Cute · Casual

MyVoiceZoo
Shared: Creature Collector · Casual · Idler

How to Train Your Cock
Shared: Desktop Companion · Idler · Casual