This song seems like it could be about an FWB relationship. He's her best kept secret because the arrangement is that they don't tell anyone about their casual hookups where he makes her feel things that she's never felt, both physically and emotionally. Part of the agreed arrangement is not to kiss but she's fallen for him and wants, more than anything, to kiss him. All she can do is dream about it. She's either thinking this to herself or finally telling him how she feels.
This song seems like it could be about an FWB relationship. He's her best kept secret because the arrangement is that they don't tell anyone about their casual hookups where he makes her feel things that she's never felt, both physically and emotionally. Part of the agreed arrangement is not to kiss but she's fallen for him and wants, more than anything, to kiss him. All she can do is dream about it. She's either thinking this to herself or finally telling him how she feels.