Rust's Links
Rust only feels any connection to koi, koi has been with him through the toughest of his times and hopes she will forever be by his side. Rust struggles to interact with others unless there's something to benefit from, but with Koi he knows she is the most valuable connection he has in his life.
Koi looks up to her father with a large admiration for him. He alone has raised and cared her since her hatching day. Since it is obvious that she is a hybrid, she is very thankful to Rust for treating her with respect and equality. Koi respects him greatly and enjoys helping him with his trade.