>>55980374You're just asking about how collabing works on the Internet. Of course it's fucking free but there's often the unspoken agreement of "you scratch my back, I scratch yours" and also, the person has to agree you are worth their free time. Luckily, because it's a Japanese company, most low-tier members know their place enough to not ask high-status members for collabs to avoid burdening them with responsibility of rejecting a collab.
A lot of members specifically turn down collabs frequently or only are interested in collabs that already cross over into their interests. Most people just collab with their friends. An interesting of a constant collab couple for me is Azki/Iroha because as far as I remember they always put their songs on Iroha's channel but the karaokes go on Azki's channel. Clearly they work something like that out between themselves.