(I’m answering this from the perspective of a romantic relationship.) Love. Respect. Acceptance. Support. Emotional Intimacy. Physical Intimacy, including both sensual/sexual and non-sexual touch. An enthusiastic and mutually satisfying sex life. A desire to spend time together, and for that time to increase over the course of the relationship. Enjoyment in spending time together, regardless of activity. The intangible mushy fuzzy goofy silly lovey-dovey mildly obsessive feeling that makes something Romantic for me. The potential for life-entwinement, specifically including the ability to build a home together. The ability to spend nights together, to travel together, to spend holidays together, to appear in public together. A sense of stability or predictability, the ability to envision a future together.