<p>I usually think that fusions, as well as gems, can have whatever look they want. But they choose to respect their original form out of respect. Remember that Pink Diamond is the only gem on the series that have been reformed into a completely different form. Maybe it has some compensations. For example, as Pink gained mass when losing height (to look as a Quartz), Steg would gain height or muscular mass if he lost his extra arms.
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