Hourou Musuko, Koimonogatari Recommendations
Both are slice of life and deal heavily with introspection and LGBT issues.
However, Hourou Musuko is focused on transgendered youths, following them through life from elementary to high school. Koimonogatari is focused on the psychology and complications of being gay.
H.M. is also written from the perspective of the LGBT individuals themselves where as Koimonogatari is most often more from an outsider's perspective looking in.