Muscle lump on ribs under right pec

[iwantmusclespls]

I've got a muscle lump under my right pec. Its connected to my pec but i dont have it under my other pec. It feels like a muscle when i tense my pecs. I really dont like it because my other pec looks more roundly shaped while this one looks more like a triangle. Could this be the result of incorrect form, genetics or due to an injury? please help

- the picture is not me, its one i took from an older thread where no clear answers were given

[userJFMMADG7K7A]

I have the exact same thing I have no idea what it is it’s like another ab or something bc it flexes like an ab for me