If you're looking for manga similar to Thomas no Shinzou, you might like these titles. All recommendations are made by Anime-Planet users like you!
When nobleman and gypsy-born Serge Batouille arrived at Laconblade Academy, he had no idea his life would change forever. Upon arriving, he is roomed with the sexually-voracious and flirtatious Gilbert Cocteau, which ensures that life at the prestigious school will dole out more complications and confrontations than either boy has dealt with in the past. Together, these two young men brave love, growth, and the pain of youth, all while growing closer together than anyone would have thought...
Kaze to Ki no Uta and Heart of Thomas are so alike both in terms of artwork and plot that they could very well be the work of the same mangaka. Both are seminal yaoi manga in yaoi about schoolboys in a boarding school, the shoujo asthetics are the same as is the dreamy nostalgia that pervades the two. They even take place in a European setting in the past. More, the way the drama ties in with emotional anguish and the psychological approach make these two titles a perfect match. Fans of one ought to give the other one a go.
Fifteen-year-old Marion is intelligent, handsome and loved by everyone at his French boarding school, but the boy holds nothing but disdain for both his classmates, and himself. For Marion is devoted to rationalism, believing that emotions such as anger and love are unnecessary – even sex is merely a means of ensuring a species' survival. But deep down, this attitude is simply a façade that was carefully constructed to protect Marion's naivety and fragile emotions, and when a chance encounter brings a seductive adult woman into his life, even he won't be able to retain his icy exterior…