Disclaimer:

Currently incomplete and updates are on hiatus. Resumption is subject to my whim.

The VRMMO action game, FWO (Fantasy World Online).

In FWO, the protagonist, who chose the Summoner class—widely considered a "trap" class—collects fluffy summoned monsters and cute equipment, plays with them, and smiles to himself.

Personally, he has no particular aim to become the strongest or to actively clear content. However, he finds himself bustling about in search of cute monsters and materials for outfits, inadvertently takes on bosses, and as he gets swept up in circumstances, he eventually realizes he's become a top-ranked player in FWO.

...Or rather, his summoned monsters have (primarily rabbits).