TOuya and GAku are the ToGabito (Sinners), and they often talk about each other in their streams.
They also go to each other's house often -- basically they're really good friends.
The chat, however, thinks they're more than "just friends".
Kenmochi Touya: https://www.youtube.com/channel/UCv1fFr156jc65EMiLbaLImw
Fushimi Gaku: https://www.youtube.com/channel/UCXU7YYxy_iQd3ulXyO-zC2w
Their first collab: https://www.youtube.com/watch?v=LTtmCDpy1F4
Their second collab: https://www.youtube.com/watch?v=3iiLih6mOaU
One year later: https://www.youtube.com/watch?v=9ceIieJHgOU
Recalling their first meeting: https://www.youtube.com/watch?v=DKdDnlCE2Ak