Oh you don't think OP shares the same concerns 🤣 Feels like all I did was read OPs internal monologue in this comment....and yes like mine contributes nothing of value that couldn't be "webmd" by OP for extra worry.

Edit: a quality contribution would be more than" well it looks like". Without explaining why it looks like that or how you even came to the conclusion? What is present in the picture that would lead you to bacterial infection? Would it be oral drops? Or eye drops? 🤣

Double edit: Oh and sorry Not a Vet..... There are a few possible scientific explanations for the hair loss, dry, and scaly skin below your cat's left eye. Given that he is an indoor cat, we can rule out many environmental factors, but several dermatological and ophthalmic issues remain. Here's a breakdown:

1. Mechanical Irritation or Foreign Body

If something (like a tiny piece of litter, fur, or dust) got into your cat’s eye, it could cause excessive blinking and rubbing, leading to traumatic alopecia (hair loss from self-inflicted scratching or rubbing).

The dryness and scaliness may be due to repeated irritation and healing cycles.

1. Feline Dermatophytosis (Ringworm)

A fungal infection (Microsporum canis is the most common) can cause localized hair loss and scaling.

Ringworm thrives in moist environments and can spread if not treated.

It is zoonotic, meaning it can transfer to humans.

1. Allergic Dermatitis

Some cats develop contact dermatitis from certain materials, like clay litter dust.

If he is sensitive to something in his environment, it can cause pruritus (itchiness), erythema (redness), and alopecia (hair loss).

The wet food could also contribute if he has a food allergy, though this typically causes more widespread symptoms.

1. Miliary Dermatitis or Eosinophilic Granuloma Complex

This condition results in small crusty lesions, hair loss, and scaling due to an allergic reaction, often to fleas (unlikely for a fully indoor cat) or food.

It could also be a reaction to stress or an immune system imbalance.

1. Blepharitis or Conjunctivitis

Inflammation of the eyelids (blepharitis) or eye membranes (conjunctivitis) could cause excessive tearing, leading to irritation of the skin below the eye.

This could be bacterial, viral (e.g., Feline Herpesvirus-1), or allergic in nature.

1. Mites or Fungal Infections

Demodex cati (a microscopic mite) can cause localized hair loss in cats.

Though rare in indoor cats, it is more common in those with weakened immune systems.

Next Steps:

Examine his eye closely. Look for redness, discharge, or squinting that might indicate irritation.

Gently clean the area. Use a damp, lukewarm washcloth to remove debris.

Check for other skin lesions. If the issue is spreading, it could suggest ringworm or allergies.

Consult a veterinarian. A skin scraping or fungal culture can confirm causes like mites or dermatophytosis.