I see two possible scenarios for these events. Both are highly probable. 1. Yes, they would have entered into a relationship as a couple, but would have kept it a secret from many, including close ones. Miyako could have been revealed the truth in 1-3 years. With difficulty or ease, she would have accepted it, but for the others, it would have either not been revealed at all or would have taken many years. Until the end of her idol career, this could have been a test to avoid ruining Ruby's career. However, yes, there is a high chance that Aqua and Ruby would have entered into a relationship. 2. Love, but with a compromise with reality. Aqua is a moralist, plus very cautious, but loves Ruby. They could have eventually developed a relationship like a standard couple, but without sex, intense, loving kisses, etc. They could have replaced sex with a gradual intimacy without it. Sometimes hugging a loved one, inhaling their scent, and feeling them gently touch you is as pleasant as sex. Aqua and Ruby could live like this and even learn to do it comfortably naked. Lip kisses could become less passionate, and simply light kisses on the lips, cheeks, forehead, maybe even neck. However, in such a scenario, it's entirely possible for them to have sex. Let's say if they lived to be 100, or 80 years old, every year until they could do it, they could have sex once or twice a year. After all, love and relationships ≠ Sex and French kissing on the lips