These are 2 manga's I really liked and actually just are supposed to go together. (You can find any series I post on mangago)
Love Masshigura! by Takazawa Taeko
Plot - 1) Takaya, a high school student, has a relationship with his teacher, Hikaru. As far as Takaya knows, they're still going strong. But then he sees Hikaru with a woman ... ?! 2) This second chapter is about Hikaru's younger brother, Sora. He leaves home I personally just loved the second chapter about Sora, but it never finished with the translation I think, and will probably never update, but still a good read.
Motto Aishiaimasho by Takazawa Taeko
Plot - Keichi and Sora live a happy life now that they've moved in together. Keichi work as a director at a design office and Sora works as a hostess in a bar while attending university. The odd thing about all that is they're both men, and there's a third person coming in between them. Can Sora and Keichi struggle to live their happy lives in peace, or will the third person win...? This is the continuation of the chapter 2 story from Love Masshigura, and I love it! Just a cute read, and ofcourse I love some age difference~