The overly attached friend trope in any romance manga is almost never done well. It doesn't matter if they are gay or straight. They try to intervene in their friend's love life, threaten to use physical violence when their love rival seems to be getting closer to their beloved's affection, without being up front with their own feelings. The worst part is the aftermath, where despite all the damage they tried to inflict on a budding relationship between their crush and the love rival, they are not reprimanded and instead are validated. They are still part of their beloved friend's personal life, and they continue to intervene in minute ways, even when they "accept" that they themselves can't be in the relationship. I would be very surprised if this manga diverges in any meaningful way from what I just said.