Why do my boyfriend come in the house the next morning and balls very very tight?

If your boyfriend's testicles feel very tight the next morning, it could be due to various reasons, such as increased blood flow, arousal, or even a reaction to cold temperatures. Tightness can also occur due to anxiety or physical strain. If this tightness is accompanied by pain or discomfort, it may be advisable for him to consult a healthcare professional for further evaluation.