You get into an auto at Kankarbagh. Somebody sits down beside you and you smell fried onion and mustard oil on their shirt. Strong. You wonder how they haven't noticed.
They haven't noticed because it is on them all day. Your nose gives up on a smell it has been soaked in for twenty minutes. Theirs gave up hours ago. Yours does the same thing at home, every evening, standing at the stove.
So the honest question is not whether their shirt smells. It is what yours smells like to the person sitting next to you.
Mustard oil does not stay in the kadhai
We heat sarson oil until it smokes. That is how it is done in a Bihari kitchen, because raw mustard oil is sharp and the smoke takes the sharpness out. The moment it smokes, part of it leaves the pan.
Not as a gas. As droplets. A fine oil mist, small enough to hang in the air and drift with it. Add the tadka going into hot oil, the jeera cracking, the hing, the onion browning, and you have a room full of airborne fat.
That mist lands on everything. You can feel it on the kitchen switchboard after a few months, that slight tack under your finger. The same layer is landing on your kurta while you cook. On the dupatta over your shoulder. On the shirt hanging on the back of the kitchen door because that is where you left it.
Cloth is worse than a switchboard. A switchboard is flat. Cloth is thousands of fibres with air between them, and the mist settles into all of it.
The smell gets stronger in the almirah
Here is the part that catches people out. You fold that kurta, put it away, take it out on Thursday, and it smells worse than it did on Sunday.
Fresh oil barely smells. Old oil does. Once that film sits on cloth with air around it, it oxidises, exactly the way an open bottle of oil in your kitchen goes off. Oxidised fat is what gives you that flat, stale, slightly sour kitchen smell. The clothes were not holding a smell. They were holding oil, and the oil made the smell later.
August in Patna speeds this up. Heat drives the reaction. Humidity keeps the fibre swollen and soft and open. A closed almirah with no air movement finishes the job, and then the smell moves sideways into the folded clothes touching it.
Why the bucket did not get it out
You washed it. It came back smelling faintly of the kitchen anyway. Nothing was wrong with your washing. The problem is what you were washing.
Detergent lifts oil by surrounding it, and it needs warmth to do that. Patna tap water in a bucket sits around 30 degrees in summer and lower in winter, and at that temperature detergent moves slowly against an aged, oxidised film that has bonded into the fibre. One quick wash pulls off most of it and leaves the rest.
Fabric matters too. A cotton kurta gives the oil up reasonably well. Polyester does not. Polyester is oil-loving at the molecular level, so your synthetic kurti, your leggings, your polyester saree and your nylon dupatta grip kitchen oil hard and hold it through wash after wash. This is the same reason a gym t-shirt keeps its smell when a cotton one loses it.
And airing does not save you. Airing a shirt on the balcony works for sweat, because sweat smells are volatile and they leave. An oil film does not evaporate. It sits there and waits.
What actually works
Wash it soon. A kitchen kurta washed the same night is a normal wash. The same kurta washed next Sunday is a stain. Oxidation is a clock, and it starts when you switch off the stove.
Use warm water. Not boiling. Water you can just hold your hand in, roughly 40 degrees. Two mugs of hot water into a bucket of tap water is enough. That single change does more than any new detergent.
Give it fifteen minutes, not overnight. Detergent in warm water needs a little time to break the film. It does not need eight hours, and long soaking in a warm Patna bucket brings its own problems.
Treat the splash separately. For the actual oil spot on the front of the kurta, rub in a drop of dishwash liquid, wait five minutes, then wash. Dishwash liquid is built to cut cooking fat. Test it on a hidden corner of anything dark first.
Keep the drying rack out of the kitchen. In the rains, everyone drags the stand indoors, and the kitchen is the warmest room with the driest air. So your clean clothes hang there and get coated while they dry. Put them anywhere else. A bedroom with a fan running beats a kitchen with a stove going.
Shut the bedroom door before you start frying. In a two-room flat in Rajendra Nagar or a PG off Bailey Road, an open almirah in the same air as an open kadhai will smell like the kadhai. Close the door, open the kitchen window, and the mist mostly leaves through the window instead of through your clothes.
None of this asks you to cook less or fry less. Mustard oil is the point of the food. Just stop letting your clothes stand in the smoke, and wash them while the oil is still young.