NEED HELP: Looking for old manga, might be classic one

First of all, I’m not sure if the one I’m looking for is fall into yaoi or bara (or shounen or shota idk). Everything based on my fuzzy memory from almost 10 years ago.

There is two manga that i’m searching for:

The first one is almost fall into comedy and absurd category. One nerd guy (might be wearing glass?, and he is the tallest one), and the other one is the type of sportsman (he is shorter, but his body is visibly has more defined muscle). I’m not sure if wether the third character exist (or not) in this manga. I don’t know how it start, but in the end, they seems like to be jerking off together in one room. The key scene is the nerd one somehow lost his control over lust. Seeing the gap between the sportman thigh, the nerd got and idea. He decided to aprroach the sporst man from behind and put his D between the sportman thigh gap (yes, thigh gap, not the hole). Since the nerd has the biggest D, his D can reach sportman D even from from behind. Another memory on this manga is, there is the balloon dialogue on the sportsman that says “ore!! ore!! ore!!” while he doing the deed. Another thing that i can remember is the sportman is the first one to cum, still hard, and decided to cum again in comedic manner.

The second one is more melancholy and slow between younger and older boy. The graphic is also more detailed here and the pacing is slower. Older boy arrived on home from somewhere. They decided to take bath together. At first nothing happen, but seems like the younger one a bit curious about the older body while taking bath (secretly taking a peek multiple time?). Older one decided to show his body (“if you older you can do this”, while peeling the tip off). The younger one (with sparkling eyes i think) decided to keep touch older soft dick, and it makes the D hard. There is the dialogue that the old one says, something along “if it hard, you need to take responbilities”. Later in night, the younger one cannot sleep. Going outside, he see the light from older room is still one. He want to surprise the older one, since the door is not totally shut. When he take a peek, he found out that the older one is in the middle of jerking off. I totally forget what happen next.

That’s all I can remember. Please help me find both manga title.