Help please

Hello, I'm trying to find this bl manga/manhwa. I only saw a vid of it and I forgot to check the sauce. It started at high school the mc was tall and there is this smaller guy who is kinda flirty with him who wears glasses then years later they met at a office and the smaller guy looks different cause he becomes taller and buff than him. It's like a bottom to top transformation that's what happened. I'm not really sure about the plot cause there was no context shown on the vid. The story was also not colored but black and white so if anyone knows or has an idea about it I'll appreciate your comments. Thank you in advance! (=・ω・=)