Circle is Moon Earth (Seika Takazawa). Published 1999.
This one is a strange one. It seems Trowa is a dark angel (well he has black wings) who wants Heero. Heero resists and Trowa resorts to tentacle sex. (Yep, you read that correctly). So while Heero is getting throughly groped and screwed by tentacles, he finally surrenders to Trowa.
Next day Heero wakes up, not sure if it was all a dream. It's not until Trowa sprouts wings that he knows it really happened. Or wait ... was THAT the dream? Heero wakes up clutching his pillow in a panic. Trowa calms him down and a few feathers turn up out of nowhere. Spooky, eh?
Circle is Finder-W. Published 1998.
Trowa and Heero are a lovely couple. After blissing out on love and seeing a news story on Relena, Heero gets dressed and goes for a walk. He finds a kitten and some street toughs try to mug him. He (and Trowa who walks up upon the scene) proceed to kick bad guy butt! But one guy gets the drop on Heero and knocks him unconscious.
Trowa waits for Heero to come to (the kitten is patiently waiting too), and they have a serious talk about Heero's past with Odin Lowe (at least that's who that looks like to me). They go home together with kitten in tow.
The final story is Heero and Trowa having a romantic dinner and Trowa sweeping Heero off his feet and into the bedroom for some tasteful yaoi.
Circle is T. Fujisawa. Published 1995.
A lot of the gag humor in this doujinshi does center around Trowa. Nothing very shounen-ai except for one where there's a bad storm and Quatre is clinging onto Heero, much to Heero's distain.
There's a karaoke section where all the boys get up and sing. A gag where the boys seem to compare underwear. An overall fun dj.
Circle is Moon Earth. Published 1999.
Heero is on assignment dressed as a girl. Trowa's also at the same school (college?) undercover. They literally bump into each other in the hallway. After getting over the initial shock of running into each other, Trowa finds he can't resist Heero in a skirt. Umm... (all together now) Let the Games begin! Last page shows Quatre looking in a closet for something to wear and Wufei sweatdropping.
Circle is Moon Earth (Seika Takazawa). Published 1999.
Heero is injured from his self destruct days, but only the arm is damaged. He's scoping out the Ozzies outdoors when Trowa arrives. Trowa strips down to take a shower and Heero sees the scars on Trowa's back. He gently kisses the scars and bobs your uncle, the humpty dance begins. Afterwards, Trowa rebandages Heero's arm.