It was probably an -end of volume extra- oneshot from a very cute shounen-ai manga (could be mild yaoi)

It had something to do with a guy who was a stationery item designer but things weren't going well for him and none of his ideas were being accepted by the boss (or the sales were low). Also he had a mechanical pencil which was given to him by his ex-boyfriend (I think it had glitter and stars on it). He then submits a new design based on that pencil and the product sells quite well.
I don't even remember if his ex came in the story.

Additional info: the art was pretty clean and a bit sketchy I guess (and I feel like it was a lot like Nojiko's art---but I'm not sure). Also I remember this scene of him slightly leaning on a road side pole and looking at the sky and thinking ...
His office was quite small and the setting was in a moderate and quite town (means he wasn't in any big city like Tokyo)

Thank you 🙂

I really want to help you since you've already helped me twice, I just read a manga where the uke gets a pen with stars on it from the seme (his former senpai) called yozora no summiko de but unfortunately that's the only theme common between your story and this one wish I could be more help!!

Thank you for replying to this post. Tbh I'd already lost hope bit I'm really really glad that there are people like you out there 🙂
I've read Yozora no summiko and it's a realy beautiful story. In fact, anything by Nojiko is worth reading.
Thank you and you were of enough help 🙂

I'm still looking for this one. Any help is appreciated 🙂