Firstly, most grasses won’t do well indoors, so you’ll probably have to go along with a look-alike. Secondly, I don’t have edibility info on the plants I will recommend. Do not ingest any parts of those plants until you have it from a reliable source that the part is edible.
The plants listed below should last indefinitely with proper care, rarely need trimming, and do not require full sun. They may require weekly attention, depending on how often you find you must water. They all have straight, green leaves, which usually arch some as they mature. Many of these plants are more commonly seen in their variegated forms. All of them should make a nice, green strip of wavy ‘grass’ in your living room, given good care.
My top 5 recommendations:
Carex morrowii, or Japanese sedge grass, can be unvariegated.
Not an actual grass. Easy to grow and contrasts well with broad-leaved foliage plants.

- light: bright filtered light
- temperature: 65-70° Fahrenheit, 50-60° in winter, if possible
- humidity: high, especially during warm spells
- watering: thorough, allowing top 1" of mixture to dry completely in between
- feeding: standard liquid fertilizer every 4 weeks, only during spring and summer
Chlorophytum cosmosum, or Spider Plant, can be unvariegated
Can be hard to come by. Very, very easy to grow. Good beginners plant.

- light: bright filtered light. Avoid direct summer sun.
- temperature: normal room temperatures
- humidity: not too picky, but higher humidity is beneficial
- watering: in spring and summer, keep thoroughly moist. In winter, allow top 1/2" to dry
- feeding: standard balanced fertilizer, every two weeks while actively growing
Liriope muscari, or lily-turf
Usually seen as a groundcover/border plant in outdoor beds; recently becoming a popular houseplant. Usually easy-care plant.

- light: will flower if given bright light. Tolerant of a fair amount of shade.
- temperature: tolerates fluctuations well, but needs 50-55°F during winter
- humidity: higher is beneficial, but tolerant of low humidity for periods of time
- watering: In summer, allow top 1/2" to dry between waterings; keep from drying completely in winter
- feeding: standard balanced fertilizer, every two weeks while actively growing
Ophiopogon jaburan, another lily-turf
Uncommon. I’ve had success with this, in large shallow pots, but that may not be necessary.

- light: will flower if given bright light. Tolerant of a fair amount of shade.
- temperature: tolerates up to 75°F in high humidity; likes 60-68°F if possible
- humidity: likes a high humidity, stand on a tray of pebbles
- watering: In summer, allow top 1/2" to dry between waterings; keep from drying completely in winter
- feeding: standard balanced fertilizer, every two weeks while actively growing
Stenotaphrum secundatum, or Buffalo Grass
Not a common indoor plant, but rather easy. May need occasional trimming.

- light: as bright as possible
- temperature: no lower than 55°F
- humidity: likes a high humidity: stand on a tray of pebbles
- watering: in summer, keep thoroughly moist; in winter rest, keep from drying completely
- feeding: do not overfeed; standard balanced fertilizer once every 4-5 weeks while actively growing