Welcome to health care magic.
1.The features suggest quite a big lump in the left breast with pain on touch - the possible cause in first place can be infective aetiology with collection.
2.Male breast lumps are also possible but comparatively rare.
3.In this case if you are my patient i would have examine and ask for a ultrasound
breast / lumpy area.
4.Ultrasound will help assess the nature of the lump and its source and extensions. If its a mass lesion an FNAC - fine needle aspiration cytology for nature of cells causing the lump. And treatment accordingly.
5.So suggest you to get him to your GP, get examined,investigated and treated accordingly.
Hope i have answered your query,
any thing to ask do not hesitate to ask.