Does ejaculation usually leave odor on an underwear after i came ?

Yes: There is a distinct odor for most healthy men's ejaculate. The odor can be stronger or weaker at times based on foods and beverages but there will always be a distinct, healthy odor. If the odor becomes very foul, changes suddenly or the ejaculate changes color, see your MD immediately as it can be a sign of a urinary tract infection or a sexually transmitted disease